Preheat the oven to 350°F (175°C). Grease and flour two 9-inch square cake pans.

In a large bowl, whisk together the flour, sugar, cocoa powder, baking powder, baking soda, and salt until well combined.

Add the eggs, milk, vegetable oil, and vanilla extract. Beat on medium speed for 2 minutes until smooth.

Carefully stir in the boiling water until the batter is thin and glossy.

Divide the batter evenly between the prepared pans. Bake for 30–35 minutes, or until a toothpick inserted into the center comes out clean.

Allow cakes to cool in pans for 10 minutes, then invert onto wire racks and cool completely.

For the buttercream frosting, beat the softened butter until creamy. Gradually add powdered sugar, milk, and vanilla extract, mixing until light and fluffy.

Apply a thin “crumb coat” of frosting to each cake layer. Chill for 10 minutes to set.

Stack the cakes with frosting between layers. Spread a final coat of buttercream over the top and sides.

Divide marzipan into portions. Tint each portion with green, brown, or black food coloring. Roll out to 1/4-inch thickness, then cut into small squares to mimic Minecraft pixels.

Arrange marzipan squares on the frosted cake in a pixelated pattern. Use cornstarch to prevent sticking. Chill briefly to set decoration.