Donauwelle — Danube-wave cherry chocolate cake

i. Origin & history

Donauwelle is a 20th-century German invention from the Bavaria-Württemberg region. The marbling technique gives the cake its name — the sponge bakes into wave shapes around the cherries.

ii. Ingredients

Makes 16 servings · scroll the side panel to adjust

• 250 g unsalted butter, soft
• 250 g sugar
• 4 eggs
• 350 g plain flour
• 2 tsp baking powder
• Pinch salt
• 2 tbsp milk
• 30 g cocoa
• 2 tbsp milk extra
• 400 g jarred sour cherries, drained
• 500 ml whole milk
• 100 g sugar
• 60 g cornstarch
• 2 egg yolks
• 250 g unsalted butter, soft
• 150 g dark chocolate
• 60 g unsalted butter

iii. Method

1. Cream butter and sugar; beat in eggs.
2. Divide batter in half. Mix half with flour and baking powder for vanilla; mix the other half with cocoa and extra milk for chocolate.
3. Spread vanilla layer in a lined 23 × 33 cm tin. Drop chocolate batter over in spoonfuls; swirl gently. Press cherries into the top.
4. Bake at 180 °C for 30-35 min. Cool.
5. Make pastry cream: cook milk, sugar, cornstarch, yolks to a thick custard; cool with cling film on surface.
6. Beat soft butter; gradually beat in cooled custard. Spread over the cake.
7. Melt chocolate and butter; pour over the buttercream; drag a comb or fork into wave pattern. Chill to set.

iv. Tips & common mistakes

• Use the freshest ingredients you can. The recipe relies on them.
• Read the method through first. Several steps must be ready in advance.
• Season patiently. Sweetness and salt are tuned at the end, not the start.

v. Variations

Schwarzwälder Donauwelle uses morello cherries. Modern variations use raspberries or apricots in place of cherries.

vii. More from Austrian & German

• Schwarzwälder Kirschtorte — Black Forest cherry cake
• Prinzregententorte — Bavarian seven-layer cake
• Kardinalschnitten — Cardinal's slice
• Medovik — Russian honey cake
• Topfenstrudel — quark strudel
• Apfelstrudel — apple strudel