3 best yolk buttercream Recipes

cake, all-purpose flour, plus more for pans, sugar, cocoa powder, baking soda, baking powder, kosher salt, buttermilk , shaken, vegetable oil, extra-large eggs, at room temperature, pure vanilla extract, hot coffee, semisweet chocolate (recommended ( callebaut), unsalted butter, at room temperature, extra-large egg yolk, at room temperature, pure vanilla extract, powdered sugar , sifted, instant coffee powder

egg yolks, at room temperature, sugar, vanilla, walnuts or 1 1/2 cups pecans, vanilla wafer crumbs, butter, melted, semi-sweet chocolate chips, melted, egg whites, at room temperature, sugar, butter, at room temperature, semi- sweet chocolate chips, melted, vanilla