Preheat the oven to 350°F (175°C). Grease three 8-inch round cake pans. Line the bottoms with rounds of parchment paper, then grease the parchment as well. Set aside.

In a medium bowl, whisk together the flour, cocoa powder, baking powder, baking soda, and salt. Set aside.

In a large mixing bowl, beat the softened butter with an electric mixer for one minute. Add the granulated sugar and beat for about 2 to 3 minutes, until light and creamy.

Add the eggs one at a time, mixing well after each addition and scraping down the sides of the bowl as necessary. Along with the final egg, you can add the vanilla and mix to combine.

Add the sour cream and mix.

Add the dry ingredients to the butter mixture in three additions, alternating with the milk. Begin and end with the dry ingredients. Mix on low speed just until combined after each addition. Avoid overmixing.

Slowly pour in the hot coffee, or water, while mixing on low speed. Mix just until the batter is smooth and evenly combined. The batter will be relatively thin.

Divide the batter evenly between the three prepared 8-inch pans. For the most even layers, weigh the batter and divide it equally among the pans.

Bake at 350°F (175°C) for approximately 25 to 30 minutes, or until a toothpick inserted into the center comes out clean or with a few moist crumbs.

For a more precise indication of doneness, the internal temperature in the center of the cakes should be approximately 200–205°F (93–96°C).

Let the cakes cool in the pans for about 10 minutes, then carefully turn them out onto a cooling rack and remove the parchment paper. Allow the cake layers to cool completely before assembling.

Add the water, granulated sugar, and cocoa powder to a small saucepan.

Place over medium heat and whisk until the cocoa powder is incorporated and the sugar has dissolved.

Bring the mixture to a gentle simmer and cook for about 1 to 2 minutes, whisking occasionally, until smooth.

Remove from the heat and transfer the syrup to a heatproof container.

Allow the chocolate syrup to cool completely before using it on the cake. Do not pour warm syrup over the cake layers.

The syrup can be made ahead of time and stored in an airtight container in the refrigerator. Refrigerate for up to about 1 week. Let it come closer to room temperature before using if it becomes thicker when chilled.

Add the diced strawberries, sugar, and lemon juice to a saucepan. Cook over medium-high heat, stirring occasionally.

Once the strawberries come to a boil, reduce the heat to medium-low. Continue cooking, stirring occasionally, until the strawberries soften, release their juices, and the sauce begins to thicken.

Cook until the strawberries are very soft and the mixture has reduced into a thick sauce, about 10–15 minutes. You can gently mash the strawberries with the spatula as they cook.

If using whole frozen strawberries, cook a bit longer so they have a chance to dissolve in the sauce.

If the mixture begins sticking to the pan, reduce the heat.

In a small bowl, mix the cornstarch and water until completely smooth. Pour the slurry into the strawberry mixture.

Cook for another 1–2 minutes, stirring constantly, until the sauce thickens.

Remove from the heat and transfer to a bowl. Place plastic wrap directly on the surface and let it cool completely. Refrigerate until chilled before using.

Continue cooking for about 15 minutes, or until the brigadeiro has thickened considerably. It should fall from the spatula in a slow, thick flow and thickly coat the back of a spoon. Remove from the heat and set aside while you prepare the ganache.

Make the ganache: Place the chopped chocolate in a large heatproof bowl and melt it gently in the microwave in 20-second intervals, stirring between each interval, or over a double boiler.

Heat the heavy cream until it reaches approximately 105°F (40°C). Pour the warm cream over the melted chocolate and whisk gently until completely smooth and glossy.

Add the brigadeiro and ganache to a large mixing bowl. Using an electric mixer, beat on low speed for about 2 minutes, until the mixture is completely smooth and evenly combined.

Cover the bowl with plastic wrap and leave the Brigadeiro Ganache at room temperature for about 4 hours, or until it has cooled completely and reached a thick, spreadable consistency.

If you refrigerate the ganache, it will become quite firm. Remove it from the refrigerator at least 2-4 hours before using so it can soften and return to a spreadable consistency.

Make sure the cake layers, strawberry sauce, chocolate soaking syrup, and Brigadeiro Ganache are all completely cool before assembling the cake.

Transfer some of the Brigadeiro Ganache to a piping bag fitted with a piping tip, or simply cut the end of the piping bag. I used a wilton 4B because that’s what I wanted to use to pipe the swirls on top.

Place the first chocolate cake layer on a cake board or serving plate. Slice off the domed top of the cake with a serrated knife, if necessary, to create a flat, even surface before adding the filling.

Brush the top of the cake layer generously with the chocolate soaking syrup. Make sure the cake absorbs the syrup before proceeding.

Spread a thin layer of Brigadeiro Ganache over the top of the cake.

Pipe a border of Brigadeiro Ganache around the outer edge of the cake layer. This will create a dam to keep the strawberry filling from spilling out.

Spoon half of the strawberry sauce inside the Brigadeiro Ganache border and spread it evenly.

Place the second cake layer on top. Brush with chocolate soaking syrup, spread with another thin layer of Brigadeiro Ganache, pipe a border around the edge, and fill the center with the remaining strawberry sauce.

Place the final cake layer on top. Refrigerate the assembled cake for at least 20 minutes. Chilling the cake at this stage will help stabilize the layers and make it much easier to frost.

Remove the cake from the refrigerator and spread the Brigadeiro Ganache over the top and sides of the cake.

If the Brigadeiro Ganache has become too firm to spread smoothly, place about 3 tablespoons of the frosting in a small microwave-safe bowl and heat it very gently for just a few seconds, until slightly softened. Return the warmed frosting to the remaining Brigadeiro Ganache and mix until the entire batch becomes a little softer and easier to spread.

Use an offset spatula to spread the Brigadeiro Ganache evenly over the top and sides of the cake, smoothing the surface as desired.

Transfer some of the remaining Brigadeiro Ganache to a piping bag and pipe decorations over the top of the cake. I used a tip 4B.

Decorate with fresh strawberries and brigadeiros (recipe here).

For chocolate curls, run a vegetable peeler along the side of a chocolate bar and scatter the curls over the cake. I like using Lindt milk chocolate because it makes beautiful chocolate curls.

Finish with chocolate sprinkles or flakes if desired. I used Cacao Barry chocolate flakes, which I purchase from OliveNation.

Refrigerate the cake for at least two hours before serving.