Preheat your oven to 350 degrees Fahrenheit and position the rack in the center. Line the bottoms of two 9-inch round cake pans with parchment paper and lightly grease the sides.

In a large mixing bowl, whisk together flour, sugar, cocoa powder, baking soda, baking powder, and salt until well combined.

In a medium bowl, whisk together eggs, cooled coffee, buttermilk, vegetable oil, and vanilla extract until the mixture is smooth.

Pour the wet mixture into the dry ingredients and stir with an electric mixer on medium speed for about two minutes until just combined.

Pour the batter evenly between the prepared pans and tap them gently on the counter to remove air bubbles. Bake for 28 to 32 minutes.

Remove the pans from the oven and let them cool for 10 minutes at room temperature before turning the layers out onto cooling racks.

Spread toffee bits and sliced almonds on a shallow baking pan and drizzle with melted butter and brown sugar, stirring gently to coat. Toast in a 325-degree oven for 5 to 7 minutes.

Using an electric mixer, beat softened butter on medium-high speed for about 3 minutes until pale and fluffy. Add cocoa powder and beat for another minute.

Gradually add powdered sugar, heavy cream, vanilla, and salt, beating until the frosting reaches a smooth, spreadable consistency.

Place one cooled cake layer on your serving plate and spread about one-third of the frosting on top. Top with the second cake layer and frost the top and sides with the remaining frosting.

Press the cooled toffee crunch mixture gently onto the frosted cake, covering the top and sides.