INGREDIENTS
8tablespoons (1 stick) unsalted butter, plus extra for coating
3tablespoons all-purpose flour, plus extra for dusting
1/2cup sugar, plus extra for dusting
10 ounces semisweet chocolate, coarsely chopped
4 large eggs
1 large egg yolk
1teaspoon vanilla extract
1/4teaspoon salt
1/2cup mini marshmallows
2tablespoons unsweetened cocoa powder