Preheat oven to 200°C (400°F) and line three 8 x 8-inch pans with parchment paper.
Mix almond flour, powdered sugar, and all-purpose flour in a bowl; add whole eggs and mix until smooth.
In a separate bowl, beat egg whites with salt to soft peaks, add sugar, and beat to stiff peaks.
Fold egg whites into almond mixture, then gently mix in melted butter.
Divide batter evenly into pans and bake for 9–10 minutes, until a skewer comes out clean. Let cool.
Simmer water, sugar, coffee, and Cointreau (if using) to make coffee syrup; let cool.
Melt chocolate in microwave, add cream, and stir into a smooth ganache. Let it cool.
Mix espresso powder with milk.
In a stand mixer, beat butter until fluffy, add powdered sugar, then espresso-milk and vanilla to make coffee buttercream.
Place one cake layer on a board, brush with coffee syrup, and spread with half the buttercream.
Add second cake layer, brush with syrup, and spread with chocolate ganache.
Add third cake layer, brush with syrup, and spread remaining buttercream on top and chill cake for at least 2 hours.
Melt chocolate for glaze, whisk in coconut oil, and pour over chilled cake on a wire rack.
Refrigerate until set, slice, and serve.