Preheat your oven to 350°F (175°C) and prepare your baking dish by greasing and flouring a 9x13-inch dish.

In a medium bowl, whisk together the all-purpose flour, baking powder, and salt. Set aside.

In a large mixing bowl, cream the softened unsalted butter and granulated sugar together until light and fluffy, about 3-5 minutes.

Add the large eggs one at a time to the butter-sugar mixture, mixing well after each addition, then stir in the vanilla extract.

Gradually add the dry ingredients to the butter mixture, alternating with the whole milk until smooth.

Pour the batter into the prepared baking dish and bake for 25-30 minutes or until a toothpick comes out clean.

Let the cake cool completely in the pan.

Whisk together the sweetened condensed milk, evaporated milk, and heavy cream in a separate bowl.

Poke holes in the cooled cake with a skewer and pour the milk mixture over it slowly.

Cover the cake and refrigerate for at least 2 hours, ideally overnight.

Before serving, top the cake with diced ripe mango and optional mint leaves.