Frozen Chocolate Mousse (Marquise au Chocolat) | Saveur

Ingredients

• 13 oz. oz. bittersweet chocolate, chopped
• 1 stick (4 oz.) unsalted butter, cut into 16 pieces
• 4 large egg yolks, at room temperature
• 1⁄3 cup cup plus 3 Tbsp. sugar, divided
• 1⁄4 tsp. tsp. fleur de sel, or a pinch fine sea salt
• 1 1⁄4 cups cold crème fraîche, plus more for serving if desired
• 1⁄4 cup cold milk
• 12 Speculoos cookies, such as Lotus Biscoff, chopped
• 8 oz. semisweet or bittersweet chocolate, finely chopped
• 1 1⁄4 heavy cream, or more as needed