Very Chocolatey Chocolate Bar Cake

Three forms of chocolate go into this cake: solid melted chocolate bars for body, chocolate syrup for sweetness and moisture, and the dark crumb that results when both layers come together. Buttermilk and a touch of vinegar give the tender, slightly tangy texture that keeps a cake this rich from feeling oppressive.

The melted chocolate bars are the soul of this cake. Melt them gently in a double boiler or microwave at half power, stirring between bursts. Burned chocolate is bitter and grainy, and it can’t be saved. Standard milk chocolate Hershey-style bars are traditional here; semi-sweet baking bars give a more grown-up flavor.

The milk-vinegar combo creates a quick buttermilk substitute that boosts the actual buttermilk and amplifies the reaction with baking soda. Acid plus soda equals lift, which is what carries this dense batter to a properly risen cake.

Using an angel food pan (tube pan) is essential for this volume of batter. The hollow center allows heat to penetrate evenly through the thick batter; a standard bundt pan leaves a gummy center because the heat can’t reach far enough into the depth.

The 90-minute bake at 350°F (175°C) is long but necessary. Pull the cake too early and the center stays raw under a baked exterior. Test with a long skewer pushed all the way through; clean, with a few moist crumbs, is the target.

Pro Tips

• Grease the tube pan generously with butter, then dust with cocoa powder (not flour) for clean release and no white streaks.
• Let the cake cool 15 minutes in the pan before turning out; warm cake breaks.
• Dust the cooled cake with powdered sugar, or drizzle with a simple chocolate glaze.
• Wrap and rest overnight; the flavor deepens significantly.

Variations

• Stir a cup of chopped walnuts or pecans into the batter for crunch.
• Use white chocolate bars instead of dark for a different effect.
• Add a teaspoon of espresso powder to amplify the chocolate notes without adding coffee flavor.