Preheat oven to 350F. Grease a 9x13 inch baking dish. Feel free to use a parchment paper too if you'd like, it's not a must.
In a medium bowl, whisk together the flour, baking powder, and salt. Set aside.
1 cup all-purpose flour, 1 1/2 tsp baking powder, 1/4 tsp salt
In a large bowl, beat the egg yolks with the 3/4 cup sugar until pale and thickened, about 2 to 3 minutes.
5 large eggs, 3/4 cup granulated sugar
Mix in the milk and vanilla, then fold in the dry ingredients just until no streaks remain.
1/3 cup whole milk, 1 tsp vanilla extract
In a clean bowl, whip the egg whites to soft peaks. Slowly add the remaining 1/4 cup sugar and whip to stiff, glossy peaks.
5 large eggs, 1/4 cup granulated sugar
Gently fold the egg whites into the batter in two additions, keeping as much air as possible.
Pour into the prepared pan and bake 25 to 30 minutes, until a toothpick comes out clean. Check around the 25 minute mark and even earlier if your oven runs hotter.
Let the cake cool completely in the pan, at least 1 hour.
Whisk together the evaporated milk, condensed milk, and heavy cream.
12 oz evaporated milk, 14 oz sweetened condensed milk, 1/2 cup heavy cream
Poke holes all over the cooled cake with a fork. Slowly pour the soak over the top, letting it absorb as you go.
Cover and refrigerate at least 4 hours, or overnight for best results.
When ready to serve, whip the cold heavy cream, powdered sugar, and vanilla to soft to medium peaks.
2 cups heavy whipping cream, 1/2 cup powdered sugar, 1 tsp vanilla extract
Spread or pipe the whipped cream over the chilled cake. Slice and serve cold.