Step 1
Preheat the oven to 350 degrees F (175 degrees C). Generously grease a 10-inch fluted tube pan (such as Bundt®).
Step 2
Combine condensed milk evaporated milk lime juice eggs lime zest salt and vanilla extract for flan in a large bowl; whisk until thoroughly combined. Pour mixture into the prepared pan.
Step 3
Remove 4 pineapple slices and 1/2 cup pineapple juice from the can of pineapple. Cover and place in the refrigerator to reserve for the caramel topping.
Step 4
Place remaining pineapple slices and juice in the bowl of a food processor; blend until smooth. This should result in approximately 1 1/4 cups pureed pineapple.
Step 5
Whisk flour baking powder baking soda and salt together in a small bowl until combined.
Step 6
Cream sugar and butter in a large bowl until light and fluffy. Beat in eggs 1 at a time mixing well after each addition. Mix in vanilla. Add 1/2 of the dry ingredients and mix until just combined. Stir in 1/2 of the pineapple puree until just combined. Continue adding dry ingredients alternately with pineapple puree mixing until just combined. Place large spoonfuls of cake batter over the flan layer as evenly as possible; don't worry if they mix they will separate during baking. Cover the Bundt® pan tightly with lightly greased aluminum foil and place it into a large roasting pan.
Step 7
Place in the preheated oven and fill the roasting pan with enough water to come 1/3 of the way up the sides of the Bundt® pan or at least 1 inch deep. Bake in the hot water bath until a toothpick inserted into the center comes out clean about 1 1/2 hours.
Step 8
Remove from the water bath remove aluminum foil and allow cake to cool in the pan for 1 hour. Carefully run a table knife around the edges to loosen. Invert carefully onto a serving plate or platter and allow to cool to room temperature about 30 minutes. Loosely cover cake and place into the refrigerator for 4 hours to overnight.
Step 9
Shortly before you are ready to serve the cake combine butter and brown sugar for caramel topping in a large skillet over medium-low heat. Cook stirring often until bubbling and sugar has melted about 2 minutes. Pour in reserved 1/2 cup pineapple juice; cook and stir until mixture is bubbling and thoroughly combined about 2 minutes. Add reserved pineapple slices and cook stirring the sauce frequently about 3 minutes. Flip pineapple slices over; cook and stir until sauce has thickened and turned a slightly deeper golden brown color about 3 minutes more.
Step 9
Quickly and carefully place the pineapple slices on top of the cooled cake. Spoon caramel sauce over top of the pineapple slices and cake. Garnish with lime zest and cherries.