White Chocolate–Macadamia Nut Cake with Mango | America's Test Kitchen

Ingredients

• 12 ounces (340 grams) frozen chopped mango, thawed
• ½ cup water
• ¼ cup (1¾ ounces/50 grams) sugar
• 1 tablespoon lemon juice
• 1½ cups roasted unsalted macadamia nuts, divided
• 4 ounces (113 grams) white chocolate, grated
• 1 cup (7 ounces/198 grams) sugar
• 1¼ cups (5 ounces/142 grams) cake flour
• 1½ teaspoons baking powder
• ½ teaspoon table salt
• 3 large eggs, separated, plus 2 large whites
• ½ cup vegetable oil
• ¼ cup water
• 2½ teaspoons vanilla extract
• ¼ teaspoon cream of tartar
• 1 ripe but firm mango, peeled, pitted, and sliced very thin lengthwise
• 8 ounces (227 grams) white chocolate, chopped
• ½ cup (3½ ounces/99 grams) granulated sugar
• 3 large egg whites
• ⅛ teaspoon table salt
• 16 tablespoons unsalted butter, cut into 16 pieces and softened