Preheat the oven to 350 degrees.

Grease three 9-inch round cake pans.

Add the flour, sugars, cocoa powder, baking soda, baking powder, and salt to a large bowl and whisk until combined.

In a separate bowl, whisk together the eggs, milk, Greek yogurt, water, vanilla extract, and melted butter.

Add the wet ingredients to the dry ingredients and mix with an electric mixer until just combined.

Fold in the chocolate chips.

Pour the batter evenly among the 3 cake pans.

Bake for 35 minutes or until a toothpick inserted in the center of the cake comes out clean. Let the cake cool for at least 10 minutes.

While the cake is baking and cooling, make the frosting. Start by creaming the butter until smooth with an electric mixer.

Then, sift in the powdered sugar and cocoa powder. Mix with an electric mixer until well incorporated.

Add in the vanilla extract, salt, and heavy cream and mix again until the frosting reaches a smooth and creamy consistency with stiff peaks.

Transfer 1 cake layer to a cake stand and add a layer of frosting on top. Add on the 2nd cake layer, another layer of frosting, and the 3rd layer of cake.

Then, frost the entire exterior of the cake.

Pipe designs on the top of the cake if desired. Then, add chocolate chips and sprinkles to the top and sides of the cake.