Prep Time 30 minutes mins
Cook Time 28 minutes mins
Resting Time 2 hours hrs
Total Time 2 hours hrs 58 minutes mins
Use gel food coloring for a richer hue without thinning the batter, and adjust cocoa slightly if using Dutch-process by reducing to 1.5 tablespoons to maintain brightness. Ensure the pastry cream is fully cold and thick; if loose, whisk briefly and chill 10 more minutes so it doesn’t ooze out. A frosting dam is essential when filling with pastry cream—pipe it at least 1/2 inch high. For extra moisture, brush cooled layers with a light simple syrup. If buttermilk isn’t available, substitute 1 cup milk mixed with 1 tablespoon vinegar, rest 5 minutes. Chill the assembled cake at least 30 minutes before slicing for cleaner cuts, and warm your knife in hot water, wiping between slices.