01 -
Grease three 20 cm cake pans and line bases with parchment; preheat oven to 180°C.
02 -
In a large bowl, combine cake flour, granulated sugar, cocoa powder, brown sugar, baking powder, baking soda, and salt. Add softened butter and mix on low speed until the mixture resembles coarse sand, about 3 minutes.
03 -
Whisk together sour cream, milk, eggs, oil, and vanilla. Add half to the flour mixture and mix on low speed for 1 minute to form a thick paste; scrape sides. Add the remaining wet mixture and mix until just combined. Scrape bowl.
04 -
Pour hot coffee into the batter and mix until just combined. Scrape the bowl as necessary to ensure even blending.
05 -
Divide batter evenly among prepared pans (about 490 g each). Bake for 18–25 minutes or until a toothpick inserted in the center shows moist crumbs. Cool in pans before removing.
06 -
In a saucepan over medium heat, cook strawberries, water, and lemon juice, mashing occasionally, until glossy and thickened, about 15 minutes. Reserve 60 ml for buttercream.
07 -
Add granulated and brown sugar to saucepan; cook for 3–4 minutes. Stir cornstarch into 15 ml water, add slurry to strawberry mixture, and cook 2 minutes until no longer cloudy. Transfer to a bowl and cool.
08 -
Beat unsalted butter in a stand mixer until smooth. Gradually incorporate powdered sugar and beat until light and fluffy, about 2–3 minutes. Add reserved strawberry filling one tablespoon at a time, beating well after each. Mix in vanilla and cream. Beat for 2–3 more minutes until very fluffy.
09 -
Place first cake layer on a serving plate. Pipe a buttercream border, then spread half the strawberry filling inside. Repeat with second layer. Place final cake layer upside down for an even top.
10 -
Spread remaining buttercream over top and sides for a thin, even coat. Chill cake for stability while preparing ganache.
11 -
Heat cream nearly to boiling point, pour over chopped chocolate, and let stand 1 minute. Stir until smooth and emulsified. Allow ganache to cool about 5 minutes before using.
12 -
Pour ganache over chilled cake; use an offset spatula to gently push glaze over edges. Let set 15 minutes at room temperature.
13 -
Garnish cake with whole strawberries and chocolate pieces. Let the cake set at room temperature before chilling to prevent cracking.