This tiramisu coffee crumble cake is a small batch bake serving six to eight — a moist, tender coffee and mascarpone sponge baked with a golden crumble topping, finished with a softly whipped mascarpone cream dusted generously with cocoa powder. It is three beloved bakes in one: the coffee-soaked richness of a tiramisu, the crumbly, textured topping of an American coffee cake and the simple, single-layer format of a classic British coffee cake. The sponge uses avocado oil and mascarpone in place of butter, which keeps it exceptionally moist and gives a beautifully tender crumb that improves over several days. The crumble is added halfway through baking rather than from the start — a technique that gives it a platform to rest on and keeps it crisp rather than sinking. The mascarpone cream is softly whipped and deliberately unsweetened, balancing the sweetness of the cake beneath. It is, without question, one of the most considered and most delicious things in the Small Batch Bakes series.

Why I created this recipe

This week I’d also been pondering American coffee cakes (don’t ask me why, I truly don’t know). Now you may be thinking, what could possibly be the difference between an American coffee cake and a British coffee cake- coffee is coffee, is it not? Well, my friends, the difference is that only one of these cakes actually contains coffee (and I’ll give you one guess as to which one is a misnomer). While a British coffee cake is a coffee-flavoured sponge, its American counterpart is a cake designed to be served with coffee (so it’s perhaps unfair to say it’s a misnomer because I can understand it, I just don’t necessarily agree with it).

Both have their merits, one usually being topped with a crumbly streusel topping (US) and one developing the slightly sticky layer of sweet coffee-infused sponge at the bottom of the cake (UK). I’m sure you can see why it didn’t take me long to consider combining the two into the ultimate crumble coffee cake.

But I didn’t stop there!! No sir.

I figured if I was I already mingling several bakes I may as well add in another. Enter the tiramisu. Coffee-soaked lady fingers are only a hop and a skip away from a coffee cake sponge, so taking the creamy cocoa-topped mascarpone whip from a tiramisu and splodging it on top of my coffee crumble cake really only seemed right.

Put it all together and you have my Tiramisu Crumble Coffee Cake! Let me tell you a bit more about each element.

About the Small Batch Bakes Series

Small Batch Bakes is a series dedicated to baking in smaller, more manageable quantities — recipes that give you something genuinely special without an overwhelming yield. Other recipes in the series include the perfect apple crumble, the homemade vanilla custard, the 2 ingredient ice cream, the custard cream ice cream sandwiches, the strawberry cheesecake crumble tarts and the citrus school cake — all worth exploring if you love a bake that is achievable, beautiful and perfectly sized.

The Cake: why oil + mascarpone instead of butter?

One of the joys of a tiramisu is that it gets better as the days go on and I wanted the same result for my sponge- a cake that gets better as it ages (I want that for myself too x). One way to do this is to substitute butter in a sponge for oil as oil is 100% fat, as opposed to butter which is about 80-90% fat, so the cake stays hydrated for longer. It’s the reason a pound cake often gets better the longer you leave it! I knew I wanted to have oil in the cake but I also didn’t want to lose any of the richness or flavour you would get from a dairy fat like butter.

My next move was to add mascarpone! I figured if we were already going to be using it for the cream on top then it made sense to use it in the sponge as well (also killing the food waste bird with the same stone). This also worked perfectly with my desire to include oil, as mascarpone + oil would yield the perfect balance of fat and flavour!

The result is a very tender crumb, surprisingly light and fluffy and exceptionally moist. Truly the best of all the worlds!

The Crumble Technique

Quite frankly I will never say no to a crumble addition in any bake. It can do no wrong in my eyes! The beauty of it here is that it adds a much needed bit of texture to an otherwise soft and velvety bake. It also provides a slight barrier between the sponge and the cream, meaning that if you are eating this over several days, everything retains its texture.

The one issue I ran into in testing was that initially, thanks to the very light sponge, the crumble sank into the sponge, being submerged and, while still being very delicious, losing its crunch. I combated this by thickening the sponge ever so slightly so as not to lose the light structure I had achieved, and also by baking the sponge on its own for 10 minutes before scattering the crumble on top and continuing the bake. This very slight barrier worked perfectly in creating a platform for the crumble to rest upon- a small but impactful change in the recipe!

The Cream

Though this cake would be sublime with no frosting, to really bring the tiramisu element to life there had to be a mascarpone cream on top. I kept it simple and decided not to add the eggs that can be found in the cream, opting to just use the leftover mascarpone and double cream. Plus vanilla. Always vanilla.

I also kept it unsweetened to balance with the sweetness of the cake itself however, if you are a sugar fiend then please go ahead and add a dusting of icing sugar (powdered sugar if in the US) to the whip. If you enjoy a little tipple in your dessert then you could also add a splash of marsala to the cream but if I’m honest I don’t enjoy alcohol in my sweet treats, so I left it out!

Why You'll Want to Make This Recipe

A Cake That Gets Better Every Day

The combination of oil and mascarpone in the sponge means this cake improves noticeably over the first few days — the crumb stays moist and tender, the coffee flavour deepens, and the mascarpone cream settles into something almost custardy against the surface of the cake. Make it on a Friday and it will be even better by Sunday.

Small Batch, Six to Eight Slices

Baked in a 7 inch / 20cm tin, this makes six to eight generous slices — enough for a week of puddings or a small gathering, without an overwhelming quantity that goes to waste.

The Crumble Topping

A crumble addition is never wrong, and here it is particularly right. The golden, crunchy topping provides a much-needed textural contrast to the soft, velvety sponge and the soft cream — and it acts as a slight barrier between the two, which means everything retains its texture even after several days in the fridge.

My Top Tips for the Perfect Tiramisu Coffee Crumble Cake

• Use a proper double shot of espresso — around 60ml — brewed fresh or from a coffee machine. A strong instant coffee dissolved in 60ml of hot water is a workable substitute, but a proper espresso gives a more rounded, less harsh coffee flavour. Do not reduce the quantity — the coffee flavour needs to be assertive to come through in the finished cake.
• Whisk the eggs and sugar for the full three to four minutes until the mixture is genuinely pale, thick and leaves a ribbon trail when you lift the whisk. This is the stage at which most of the air is incorporated into the cake — rushing it gives a denser, less tender crumb. Look for a mixture that is almost white and holds its shape briefly on the surface when the whisk is lifted.
• Mix the oil, mascarpone, espresso, vanilla and salt together in a separate bowl until completely smooth before adding to the egg mixture. Mascarpone is thick and can be lumpy straight from the tub — whisking it separately with the oil first ensures it incorporates smoothly into the batter rather than leaving streaks or lumps.
• Fold the oil and mascarpone mixture into the eggs gently. The eggs are the structure of this cake — over-mixing at this stage will knock out the air you have just spent several minutes incorporating.
• Sift the flour and baking powder. This is particularly important for a batter this light and aerated — unsifted flour can create pockets of dense, unmixed flour in the finished cake. Sift directly into the bowl and fold gently with a balloon whisk until just incorporated.
• Do not over-mix once the flour goes in. A few gentle folds with the balloon whisk until the flour just disappears is all that is needed — the batter should look smooth but not have been worked extensively.
• Bake for the full ten minutes before adding the crumble. Check the surface of the cake at ten minutes — it should look just set and matte rather than wet and glossy. If it still looks very liquid, give it another two minutes before adding the crumble.
• Make the crumble before you make the cake batter, so it is ready to go the moment the initial ten minutes are up. You want to add it quickly and return the tin to the oven without losing too much heat.
• Allow the cake to cool completely before adding the mascarpone cream. Adding it to a warm cake will cause the cream to melt and slide, and the cocoa dust to dissolve into it unattractively.
• To make the mascarpone cream, whisk the mascarpone, double cream and vanilla together — and icing sugar (powdered sugar) or a splash of marsala if using — until softly whipped. Do not over-whip — you want a soft, spoonable cream that sits beautifully on top of the cake, not a stiff one. Watch it carefully as it can go from softly whipped to over-whipped very quickly.
• Dust the cocoa powder generously and evenly over the cream just before serving. Use a fine sieve for the most even, elegant dusting.

Storage, Freezing & Serving

Storing in the Fridge

Once the mascarpone cream has been added, store the cake covered in the fridge for up to five days. As noted, this cake genuinely improves over the first few days — the coffee flavour deepens, the crumb stays moist and tender, and the cream settles into something almost custardy against the surface of the cake. It is worth making a day or two in advance if you are baking it for a gathering.

Freezing

If you do not think you will eat the whole cake within five days, slice it before freezing — but freeze the slices without the mascarpone cream. Wrap each slice tightly in cling film (plastic wrap) and freeze for up to three months. Defrost slices in the fridge overnight or at room temperature for a couple of hours.

Once defrosted, serve each slice with a generous spoonful of freshly made mascarpone cream on the side rather than on top — this keeps the cream at its best and means every slice gets a fresh, perfectly whipped accompaniment rather than cream that has been frozen and thawed. The cocoa dusting goes on just before eating.

Serving

This cake is delicious at room temperature but particularly good slightly chilled — the mascarpone cream firms up just enough in the fridge to hold its shape on the plate and the flavours are more pronounced when cold. Serve in generous slices with an extra dusting of cocoa if you like.

Frequently Asked Questions

Why does the crumble go on halfway through baking?

Because the sponge batter is very light and aerated — whisked to a ribbon trail before the other ingredients go in — adding the crumble from the start allows it to sink into the batter as the cake bakes, losing its crunch. Baking the sponge for ten minutes first allows the surface to just set, creating a platform for the crumble to rest on rather than sink into. It is a small step that makes a significant difference. See the full explanation in the section above.

Why does this recipe use oil instead of butter?

Oil is 100% fat, with no water content, which means an oil-based cake stays moist for considerably longer than a butter-based one. This cake is designed to improve over several days in the fridge — the oil is what makes that possible. The mascarpone compensates for the richness and dairy depth that butter would otherwise provide. See the full explanation in the section above.

Can I use a different oil?

Yes — avocado oil has a very neutral flavour and a high fat content, making it ideal here, but any neutral oil works well. Sunflower, vegetable and light olive oil are all good substitutes. Avoid strongly flavoured oils like extra virgin olive oil or coconut oil, which will affect the flavour of the finished cake.

Does the mascarpone cream need to be sweetened?

Not necessarily — the cream is deliberately unsweetened in this recipe to balance the sweetness of the sponge and crumble. If you have a sweet tooth, add icing sugar (powdered sugar) to taste. The optional marsala adds an authentic tiramisu flavour and a slight warmth — leave it out if you prefer no alcohol in your desserts.

Can I make this cake in advance?

Yes — and it is actively encouraged. This cake improves over the first two to three days as the coffee flavour deepens and the crumb stays moist. Make it a day or two before you plan to serve it for the best possible result. Store in the fridge once the cream has been added.

Is this part of the Small Batch Bakes series?

Yes — this tiramisu coffee crumble cake is the latest recipe in the Small Batch Bakes series, baked in a 7 inch / 20cm tin and serving six to eight. Other recipes in the series include the perfect apple crumble, the homemade vanilla custard, the 2 ingredient ice cream, the custard cream ice cream sandwiches, the strawberry cheesecake crumble tarts and the citrus school cake.