Use room-temperature dairy and eggs for a smooth batter and taller rise, and avoid overmixing once the flour is added to keep the crumb tender. If you prefer a darker hue, add an extra teaspoon of cocoa and a touch more red coloring, and for deeper flavor, keep the hot coffee—it enhances chocolate notes without tasting like coffee. The ganache should be peanut-butter thick before filling; if too runny, chill longer, and if too firm, microwave in 5-second bursts and stir. To prevent red crumbs in the frosting, apply a solid crumb coat and chill well before the final layer. The cake keeps covered in the fridge for up to 4 days; bring slices to room temperature for the fudgiest texture.