Chocolate Decadence for a Crowd

10 tablespoons unsalted butter, plus more for pan

10 ounces baking chocolate with 62 percent chocolate solids (“bittersweet for most brands, but “semisweet in others, like Scharffen Berger)

1 cup confectioners' sugar

4 large eggs

Heat the oven to 300 degrees. Lightly butter an 8-inch round cake pan, and line the bottom with parchment paper. Butter the parchment.

Put the butter and chocolate in a medium heatproof bowl, and place over simmering water, stirring until melted. Whisk until smooth and blended. Set aside to cool slightly.

Put cup of the confectioners' sugar and the eggs in a medium bowl. Beat with an electric mixer on medium-high speed until very thick, about three minutes. Turn the mixer to low, gradually pouring in the chocolate mixture, and continue beating until well blended. Pour the batter into the prepared pan, and spread evenly.

Bake until the top is slightly puffed and a tester comes out with gooey crumbs, about 40 minutes. Set on a rack to cool for 1½ hours. Run a knife between the cake and the inside of the pan. Invert onto a flat plate, then remove the pan and liner. Invert again onto a flat serving plate. Cool completely. Cover and refrigerate until chilled, or up to two days.

To serve: Sift the remaining cup confectioners' sugar over the top, and cut into wedges. Serve with fresh fruit or whipped cream.

Serves 10.

Cook's note: Add 1½ tablespoons dark rum or orange-flavored liqueur or 1 teaspoon of instant espresso powder, dissolved in 1½ teaspoons pure vanilla extract.

“Desserts 4 Today: Flavorful Desserts with Just Four Ingredients by Abigail Johnson Dodge (2010 Taunton Press)