Master Chocolate Nut Upside-Down Cake

Most upside-down cakes are made in a round cake pan with pineapple. This chocolate nut version goes elegant: a 10-inch Bundt pan, a deep chocolate cake batter, and a brown-sugar-and-cream-syrup base studded with walnuts that becomes a gleaming caramel crown when the cake is inverted.

The caramel layer is built on a real cream-and-corn-syrup base, not just butter and sugar. The cream is what keeps the caramel from hardening to brick consistency in the freezer; it stays glossy and slightly chewy as the cake cools. Bring the mixture just to a boil and stop; longer cooking turns it into actual caramel candy and your cake won’t release from the pan.

Separating the eggs and folding in whipped whites is what gives this Bundt its tall, cloudlike rise. It compensates for the dense chocolate-and-nut weight and prevents a gummy texture. Don’t skip the fold or rush it; gentle motions preserve the air bubbles that lift the cake.

Unsweetened chocolate is the right call. The corn syrup and brown sugar in the topping plus the granulated sugar in the cake provide all the sweetness; using semi-sweet here would push the cake into too-sweet territory.

Pro Tips

• Grease the Bundt pan obsessively. Get into every groove with melted butter or shortening; this caramel topping needs help releasing.
• Don’t pour the topping too far ahead of the batter. The caramel can start to set if it sits more than a minute or two while you finish the batter.
• Cool exactly 15 minutes before inverting. Earlier and the cake collapses; longer and the caramel sticks.
• Run a thin knife around the inner tube of the Bundt pan before flipping to release any clinging crumbs.

Variations

• Use pecans instead of walnuts for a slightly sweeter, more buttery topping.
• Add a teaspoon of espresso powder to the dry ingredients to deepen the chocolate.
• Drizzle warm chocolate ganache or dulce de leche over the cake before serving for a triple-decadent finish.