Start by making the cake. Preheat the oven to 350 degrees. Prepare a cupcake pan by lining it with cupcake liners. Mix the cake mix, pudding, eggs, sour cream, milk and oil in a standing mixer and beat until well incorporated (about 2 minutes) while scraping the sides. Fill cupcake liners 3/4 full. Place in preheated oven and bake for 18-20 minutes until tops spring back when touched.
While cupcakes are in the oven, prepare the Tres Leches mixture: mix the whole milk, evaporated milk, and condensed milk.
Remove cupcakes from oven. Immediately poke several holes in each cupcake with a skewer stick or knife.
Drizzle Tres Leches mixture over each cupcake, waiting for it to absorb, using all of the mixture evenly between eachcupcake.
Dulce de Leche Whipped Cream:
2 cups heavy whipping cream
1/4-1/2 cup dulce de leche (found in the mexican isle in the grocery store)
3 T powdered sugar (or more depending on how sweet you like it)
Combine all ingredients in a standing mixer fitted with the whisk attachment. Whisk on medium-high until soft peaks form. Pipe over cooled cupcakes. Store extra cupcakes in the fridge.