Preheat your oven according to the package instructions for the white cake mix. Grease a 9x13 inch baking dish and pour in the cake batter, smoothing the top. Bake until golden and a toothpick inserted in the center comes out clean, typically 25-30 minutes. Allow it to cool completely on a wire rack, then cut it into small cubes.

Take the cooled cake cubes and divide them evenly among 32 two-ounce plastic cups, filling each about two-thirds full. You may choose to layer the cake cubes in the cups.

In a large mixing bowl, whisk together the sweetened condensed milk, evaporated milk, whole milk, and vanilla extract until well combined and smooth. Pour this mixture into a squeeze bottle.

Evenly drizzle the milk mixture over the cubed cake in each cup, allowing the cake cubes to soak up the liquid fully. Let the cups sit for about 10 minutes.

In a chilled mixing bowl, whip the heavy cream with powdered sugar until stiff peaks form, about 3-4 minutes.

Once your whipped cream is ready, pipe or spread it evenly over the soaked cake cubes in each cup. Cover the dessert cups tightly with plastic wrap and refrigerate them overnight.