Preheat the oven to 350°F (175°C). Grease and flour a 9x13 inch baking dish.

In a bowl, whisk together flour and baking powder.

In another bowl, cream the butter and sugar until light and fluffy. Add eggs one at a time, mixing well after each addition. Stir in vanilla.

Gradually add the flour mixture to the wet ingredients, mixing until just combined.

Pour the batter into the prepared baking dish and smooth the top. Bake for 30 minutes or until a toothpick comes out clean.

In a bowl, combine evaporated milk, sweetened condensed milk, and whole milk.

Once the cake is baked and cooled, poke holes all over the top with a fork. Pour the milk mixture evenly over the cake, allowing it to soak in.

In a mixing bowl, whip the heavy cream with sugar and vanilla until soft peaks form.

Spread the whipped cream over the soaked cake and sprinkle with ground cinnamon.

Chill the cake for at least 2 hours before serving to allow flavors to meld.

Slice and serve chilled, enjoying the rich, moist texture.