Ingredients
219g (1 3/4 cups) all-purpose flour
400g (2 cups) granulated sugar
75g (3/4 cup) unsweetened cocoa powder
2 tsp baking soda
1 tsp baking powder
1 tsp kosher salt
240ml (1 cup) buttermilk, room temperature
120ml (1/2 cup) vegetable oil
2 large eggs, room temperature
2 tsp pure vanilla extract
240ml (1 cup) freshly brewed hot coffee
210g (1 1/4 cups) strawberry puree (fresh or frozen, thawed)
113g (1/2 cup) unsalted butter, softened
4 cups powdered sugar
2 tsp pure vanilla extract
28g (1 oz) white chocolate chips
140g (6 oz) white chocolate, finely chopped
113g (1/2 cup) unsalted butter, room temperature
1 tsp pure vanilla extract
Instructions
Preheat oven to 175°C (350°F). Grease and flour a 13×18-inch baking sheet.
In a bowl, sift together flour, sugar, cocoa powder, baking soda, baking powder, and salt.
Add buttermilk, vegetable oil, eggs, vanilla, and hot coffee. Whisk until smooth.
Pour batter into prepared sheet and bake for 22-25 minutes, until a toothpick inserted in center comes out clean. Let cool completely.
For ermine paste: In a large bowl, whip 210g strawberry puree until smooth. Add 113g softened butter, 4 cups powdered sugar, and 2 tsp vanilla. Beat on high speed until thick and glossy (5-7 minutes). Cover and refrigerate 45 minutes.
For white chocolate frosting: In a heatproof bowl, stir 28g white chocolate chips with 2 tbsp cream (double cream preferred) until melted and smooth. Set aside 10 minutes to thicken.
Chop 140g white chocolate into small pieces and place in a heatproof bowl with 113g butter and 1 tsp vanilla. Whisk in 1/4 cup melted strawberry-chocolate glaze, then chill in an ice bath until thickened (8-10 minutes). Whisk to stiff peaks.
Spread ermine filling over cooled cake. Top with white chocolate frosting and refrigerate 30 minutes before serving.
Notes
Chocolate cake and ermine filling can be made up to 24 hours in advance.
For egg-free option, replace 2 eggs with 120ml unsweetened applesauce.
Ermine filling freezes well for up to 2 weeks if cake is unfrosted.
Substitute buttermilk with 85ml milk + 15ml white vinegar and 60ml water for non-dairy option.
- Prep Time: 45
- Cook Time: 25
- Category: Desserts
- Method: Baking
- Cuisine: American
- Diet: Vegetarian
Nutrition
- Serving Size: 1 slice (1/20 of batch)
- Calories: 410
- Sugar: 46g
- Sodium: 380mg
- Fat: 22g
- Saturated Fat: 13g
- Carbohydrates: 52g
- Fiber: 2g
- Protein: 5g
- Cholesterol: 60mg