Preheat the oven to 350 degrees F, line a muffin tin with 12 tulip liners and lightly spray the insides of the tulip liners with cooking spray. Line another muffin tin with 6 more liners and spray.
In a large bowl, combine the flour, baking powder, and salt.
In two separate bowls, separate the egg yolks from the whites, being sure not to let any yolks get into the whites or else they won't whip properly.
Add ¾ cup sugar and the egg yolks to a stand mixer and mix on medium high speed (using the paddle attachment) until yolks are pale yellow, about 3-4 minutes. Add the ⅓ cup milk and vanilla and mix on low to combine.
Pour the egg yolk mixture over the flour mixture and gently stir by hand until combined (don’t over mix).
Using a clean, dry bowl for your stand mixer, whip (using the whisk attachment) the egg whites on high. Once soft peaks begin to form, gradually add the remaining ¼ cup sugar and continue to whip until stiff peaks form.
Fold the egg whites into the batter until just combined, careful not to stir and deflate the batter. Do this in a “J” motion, cutting down the middle of your bowl, scraping the bottom, and coming back up on the sides. The batter will be thick and fluffy. Using a large ice cream scoop or two spoons, fill each cupcake liner to half.
Bake the cupcakes for 25-30 minutes until completely set. The top of the cupcakes will be slightly browned and will look a bit shriveled. Allow the cupcakes to cool for about 10 minutes before starting to poke the holes.
While the cupcakes are resting, combine the evaporated coconut milk*, sweetened condensed coconut milk*, and whole milk in a bowl and mix by hand until it comes together.
Using a wooden skewer, poke holes all over the cupcakes the whole way down to the bottom (especially getting the sides), careful not to poke holes through the cupcake liners.
Pour 1 tablespoon of milk mixture over each cupcake and allow them to absorb the milk. Repeat this two more times (for a total of 3 tablespoons). Make sure you get the sides as best as possible.
Cover the cupcakes as best as possible and refrigerate for at least 1 hour, but preferably overnight. This allows the cupcakes to fully absorb the milk mixture.