Preheat oven to 350°F. Grease and line a 9-inch round cake pan with parchment paper.
In a bowl, whisk almond flour, cocoa powder, sweetener, baking powder, and salt.
In another bowl, whisk eggs, melted butter, almond milk, and almond extract until smooth.
Combine wet and dry ingredients, mixing until batter is smooth.
Pour batter into cake pan and smooth the top. Sprinkle sliced almonds on top.
Bake 30–35 minutes, until a toothpick inserted in the center comes out clean.
Cool completely before slicing and serving.