1.5 cups all-purpose flour
1 teaspoon baking powder
1/2 cup unsalted butter
2 cups white sugar, divided
1 1/2 teaspoons vanilla extract, divided
2 cups whole milk
14 ounces sweetened condensed milk
12 ounces evaporated milk
1.5 cups heavy whipping cream
5 eggs

Preheat the oven to 350 degrees. Grease and flour a 9-by-13 pan. Sift flour and baking powder together; set aside. Beat 1 cup of sugar and butter together in a large bowl with an electric mixer until light and fluffy. Add eggs and 1/2 teaspoon vanilla; beat well. Add flour mixture, about 1/2 cup at a time, mixing until well blended. Pour batter into the prepared pan. Bake in the preheated oven until a toothpick inserted into the center comes out clean, about 30 minutes. Pierce cake all over with a fork; let cool to room temperature. Mix whole milk, condensed milk and evaporated milk together in a bowl; pour over the top of the cooled cake and allow to soak in. Whip cream, remaining 1 cup of sugar and 1 teaspoon vanilla in a chilled glass or metal bowl with an electric mixer until thick. Spread over the top of the filling. Keep cake refrigerated until serving.