Tiramisu Layer Cake : Birthday Cake

French

This tiramisu layer cake brings together classic coffee and mascarpone flavors in a tall, clean-cut design.

The light sponge is soaked in coffee syrup, then layered with an airy mascarpone mousse.

The result is neat slices, a melt-in-the-mouth texture, and perfect stability when served.

Tiramisu Layer Cake Recipe : Coffee-Soaked Sponge + Mascarpone Mousse

For my youngest’s birthday, he’s a serious tiramisu lover, I made this mascarpone tiramisu layer cake.

Don’t let the height fool you: it’s genuinely approachable, even if you’ve never built a layer cake before.

A light sponge cake is generously brushed with coffee syrup so every bite stays moist, then stacked with an airy mascarpone mousse that tastes rich yet never heavy.

Using a cake ring and an acetate strip (rhodoïd) gives you sharp sides and clean, bakery-style slices.

Planning is easy too: bake the sponge the day before, chill it, and assemble calmly on the next day or even themorning of your celebration.

Finish with cocoa just before serving for the classic tiramisu touch.

The first slice always gets a gasp, and guests usually ask for seconds.

If you’re transporting it, keep it cold; the mousse sets beautifully after a fridge rest.

Before you start (small steps, big difference)

• Bake the sponge the day before: once fully cooled and rested, it slices into neat discs with fewer crumbs.
• Use a very large mixing bowl: the mascarpone mousse becomes voluminous (whipped cream + whipped whites).
• Weigh the empty bowl before you begin, write the number down.
• Weigh the bowl again with the finished mousse, subtract the empty-bowl weight, to have the weight of the mousse then divide by 3 for perfectly even layers.
• Layer order matters: place the most domed disc at the bottom as the base, and keep the flattest side for the top so the finished cake has a smooth surface.

Ingredients for a Perfect Tiramisu Layer Cake (20-22 cm Pan): What to Choose for the Best Result

Sponge Cake :

• 4 eggs (room temperature): whip up with more volume for a stable, well-aerated sponge.
• 120 g sugar: helps create a firm, glossy meringue and keeps the crumb soft.
• 120 g plain flour: sift if possible for a lighter texture.
• 1/2 sachet baking powder: just enough lift without an obvious “baking powder” taste.

Coffee Syrup :

• 150 ml water: the soaking base that keeps the sponge moist.
• 65 g sugar: balances the bitterness of the coffee.
• 2 tsp instant coffee: convenient and bold, stir in off the heat until fully dissolved.

Mascarpone Mousse :

• 6 eggs: yolks add richness; whites bring lightness.
• 10 g gelatin: ensures clean slices and a mousse that holds its shape.
• 200 g sugar (160 g + 40 g): 160 g for the yolks; 40 g to stabilise the whipped whites.
• 500 g mascarpone: creamy and loosened before mixing to avoid lumps.
• 270 ml very cold double/heavy cream: whips into a firm chantilly.
• 1 tsp vanilla: rounds out the flavour and perfumes the mousse.

Equipment you’ll actually use

• 20-22 cm (8-9 inch) cake pan + cooling rack
• Cake ring (same size as sponge)
• Acetate strip (rhodoid) for sharp edges and clean release
• Scale (helps split mousse evenly into 3 layers)
• Mixer/whisk + spatula
• Piping bag (for the border decoration)
• pastry brush

Step-by-step recipe (bulletproof, easy to follow)

1) Make the sponge

1. Heat the oven to 180°C / 350°F. Grease and flour the pan (or use a silicone pan).
2. Separate egg whites and yolks. Mix flour with baking powder.
3. Whip the whites to soft peaks. When foamy, add sugar gradually and whip to a firm, glossy meringue.
4. Add yolks immediately, then add the flour mixture. Mix briefly, stop as soon as combined.
5. Pour into the pan and bake 16–20 minutes (fan ovens can be faster).
6. Unmold and cool on a rack. For best slicing, chill overnight and cut into 3 discs the next day.

2) Make the coffee syrup

1. Bring water and sugar to a boil for about 5 minutes.
2. Remove from heat, stir in instant coffee until dissolved, then cool completely.

3) Make the mascarpone mousse

1. Bloom gelatin in cold water for 15 minutes.
2. Separate whites and yolks. Whisk yolks + vanilla + 160 g sugar until pale.
3. Warm 50 ml of the cream (taken from the total). Remove from heat, dissolve the squeezed gelatin in it.
4. Loosen mascarpone, then mix it into the yolk mixture.
5. Add the warm (not hot) gelatin-cream mixture.
6. Whip the remaining cream to firm peaks and fold it in gently.
7. Whip the whites, then add the remaining sugar and whip to a stable meringue.
8. Fold whites into the mascarpone mixture until light and airy.
9. Use the bowl-weighing method to split mousse evenly into 3 portions.

Assemble the tiramisu layer cake

1. Place the cake ring on a serving plate and line the inside with an acetate strip.
2. Add the first sponge disc and soak generously with coffee syrup.
3. Spread 1/3 of the mousse and smooth.
4. Add the second disc, soak, then spread the second third of mousse.
5. Add the final disc, soak, then spread half of the remaining mousse on top.
6. Put the rest of the mousse in a piping bag and keep chilled.
7. Freeze the assembled cake for at least 3 hours (for a clean unmold).
8. Unmold quickly, remove acetate, pipe the border, then refrigerate.
9. Thaw in the fridge for at least 6 hours before serving.
10. Finish with cocoa powder right before serving

Troubleshooting (quick fixes)

• Sponge collapses: overmixed after flour, mix only until combined.
• Dry sponge: overbaked or under-soaked, watch baking time closely and soak evenly.
• Grainy mousse: gelatin-cream too hot or mascarpone too cold, use warm (not hot) liquid and softened mascarpone.
• Mousse too loose: cream not cold/whipped enough, start with very cold cream and whip to firm peaks.
• Layers slip: uneven soaking or insufficient chilling, smooth each layer and respect the chilling times.

Storage, Freezing, and Transport

• In the fridge: Keep for up to 48 hours, ideally under a cake dome or well covered. Dust with cocoa right before serving.
• In the freezer: Yes, you can freeze the cake fully assembled. Wrap it well in cling film without crushing the decoration. Thaw in the fridge only, never at room temperature.
• To transport: Keep the cake very cold (ideally just out of the freezer) in a rigid cake box. For a longer journey, use an insulated bag.

Delicious Variations (Same Method, New Twist)

• Stronger coffee flavour: Add a little more instant coffee, but don’t overdo it to avoid bitterness.
• Chocolate note: Add chocolate shavings between the layers or sprinkle them on top.
• “Soft vanilla” version: Use a lighter coffee syrup and add a bit more vanilla to the mousse.
• Different finish: Pipe lines of mascarpone mousse on top, or go for a smooth, modern finish.

FAQ: Readers’ Most Common Questions

• Can I make this cake without an acetate strip (rhodoïd)?
  Yes, but the edges and unmoulding won’t be as clean. If needed, line the ring carefully with smooth baking paper.
• Why chill it in the freezer for 3 hours?
  It sets the mousse quickly, making unmoulding easier and the decoration sharper, without the sides collapsing.
• How do I get perfect slices?
  Use a long knife dipped in hot water, then wiped dry between each cut. Slice the cake when it’s very cold.
• What if I don’t have a cake ring?
  Use the ring from the springform pan you baked the sponge in. Without a ring, assembly is trickier.
• Does the sponge need to be heavily soaked?
  Yes, this is what gives the classic tiramisu softness. Soak evenly, but don’t oversaturate until the layers break.
• Can I reduce the sugar?
  A little, but it may affect texture and stability (the meringue won’t whip as firmly). Reduce gradually and test.

Other birthday Cakes to try

• Triple Chocolate Mousse Cake
• Black Forest Cake, German Dessert
• Strawberry Entremet with Mirror Glaze
• Blueberry Charlotte : An Elegant Birthday Dessert