Preheat the oven to 350°F (175°C). Prepare two 8-inch (20 cm) round baking pans by greasing the interior surfaces with butter or non-stick spray. Line the bases with parchment paper to facilitate smooth unmolding of the cakes after baking.

In a large mixing bowl, sift together the all-purpose flour, unsweetened cocoa powder, granulated sugar, baking soda, and salt. Sifting not only eliminates potential lumps but also promotes uniform distribution of the leavening agent and cocoa throughout the mixture.

In a separate bowl, combine the eggs, milk or buttermilk, vegetable oil or melted butter, and vanilla extract. Whisk the ingredients thoroughly until fully incorporated, forming a smooth and homogeneous mixture.

Gradually incorporate the wet mixture into the dry ingredients. Using a spatula or a wooden spoon, fold the ingredients together gently until just combined. Avoid overmixing, as this may result in a dense or tough texture. A few small lumps are acceptable and will dissipate during baking.

Distribute the batter evenly between the prepared baking pans. Position the pans side-by-side on the middle oven rack and bake for approximately 30 to 35 minutes. The cakes are done when a toothpick inserted into the center comes out clean or with a few moist crumbs attached.

Upon completion of baking, remove the pans from the oven and allow the cakes to cool for approximately 10 minutes within their pans. Gently loosen the edges with a knife, then invert the cakes onto wire racks to cool completely. This step is essential to prevent sogginess during the assembly process.

While the cakes are cooling, prepare the filling. Slice the fresh strawberries into small, uniform pieces. Place them in a mixing bowl and toss with 2 to 3 tablespoons of granulated sugar. Allow the mixture to sit at room temperature for 10 to 15 minutes, enabling the natural juices to be released and form a syrup.

Once the cake layers have cooled entirely, place one layer on a serving platter or cake stand. Spread half of the strawberry filling evenly across the surface. Gently position the second cake layer on top and repeat the process using the remaining filling. The assembled cake may be garnished with additional strawberry slices or lightly dusted with confectioners’ sugar if desired.