Mango Upside-Down Cake - mangoes

Method

• Standing each mango upright, remove flesh from pit by cutting a thick lengthwise slice from each broad side.
• (Be careful: Peeled mango is slippery.)
• Put slices on a work surface and cut lengthwise into 3/8-inch-thick slices.
• Melt butter in a small heavy saucepan over moderate heat, then stir in brown sugar.
• Simmer, stirring, until butter is incorporated, 1 to 2 minutes.
• Spread mixture in bottom of a buttered 9- by 2-inch round baking pan and arrange mango on top, overlapping slices.
• Preheat oven to 350F.
• Whisk together flour, baking powder, and salt.
• Beat together butter and sugar in a large bowl with an electric mixer at high speed until light and fluffy, about 6 minutes.
• Add whole egg and yolks 1 at a time, beating well after each addition.
• Beat in vanilla.
• Add half of flour mixture and mix at low speed until just combined.
• Mix in mango nectar, then add remaining flour mixture, mixing until just combined.
• Beat egg whites in another bowl with cleaned beaters until they just hold stiff peaks, then fold into batter gently but thoroughly.
• Gently spoon batter over mango topping and spread evenly.
• Bake in middle of oven until golden brown and a tester comes out clean, 55 to 60 minutes.
• Cool cake in pan on a rack 10 minutes.
• Run a thin knife around inside edge of pan, then invert a plate over pan and invert cake onto plate.
• Cool completely on plate on rack.
• Serve cake at room temperature.