Preheat to 350°. Grease 2-4, 8 inch pans with unsalted butter and line with parchment.

Bring 2 cups stout and 2 cups unsalted butter to a simmer in a medium saucepan.

Add 1½ cups cocoa powder, 4 teaspoon coffee and whisk until mixture is smooth.

Remove from heat and let cool slightly.

Meanwhile, whisk together dry ingredients in a large bowl.

Using a whisk or an electric mixer on medium-low speed, combine wet ingredients in another large bowl.

Add stout mixture and beat until combined.

Scrape down sides of bowl and add dry ingredients.

Beat or whisk on low speed until mostly combined. Using a rubber spatula, fold batter just until combined and no dry spots remain.

Divide batter evenly among prepared pans; smooth surface.

Bake cakes until a tester inserted into the center comes out clean, 30–35 minutes (40 to 45 mins if using 2 pans) let cakes cook completely.

Run an a knife or flat metal spatula around sides of cakes to loosen, then invert cakes onto a wire rack; remove parchment.

Turn cakes right side up.

Allow to cool fully.

Bring 2 cups heavy cream to a simmer in a medium saucepan.

Remove from heat and add 16 oz. bittersweet or semisweet chocolate, chopped.

Add dashes of Angostura Cocoa Bitters

Whisk until chocolate is melted and mixture is smooth.

Let cool until spreadable