PREHEAT oven to 350º F. Place mango slices in small bowl. Pour lemon juice over slices; toss lightly. Let stand for 15 minutes.
MELT butter in 9-inch-round baking pan in oven; remove from oven. Stir in brown sugar and water. Arrange mango slices in circular pattern in pan.
COMBINE flour, granulated sugar and baking powder in medium mixer bowl. Add evaporated milk, vegetable shortening, egg and vanilla extract. Beat on low speed until combined. Beat on medium speed for 1 minute. Slowly pour or spoon batter over mango slices; spread evenly.
BAKE for 30 to 35 minutes or until toothpick inserted near center comes out clean. Cool on wire rack for 5 minutes.
TO UNMOLD, run a small knife around top of cake to loosen. Place serving platter over pan; invert. (If any mango slices stick to pan, place on cake.) Serve warm or at room temperature.
FOR PINEAPPLE UPSIDE-DOWN CAKE:
SUBSTITUTE 1 can (8 ounces) pineapple slices in juice, drained, for mango and lemon juice. Cut each pineapple slice in half. Arrange slices in circular pattern. Prepare batter and bake as stated above.