Preheat oven to 350°F. Line an 8x8-inch square baking dish with parchment paper.

In a bowl, stir together all dry ingredients. In a separate bowl, whisk together egg whites, milk, oil, and vanilla. Add dry ingredients into wet, and stir until combined. Fold in optional sprinkles, if using.

Spread batter evenly into pan, and bake for 25-28 minutes. Allow to cool.

To make frosting, add cream cheese and heavy cream to a large bowl and beat with electric mixer until thick and fluffy.

Add sweetener and beat again until combined, then add liquid sweetener drops to taste.

Note: The reason for using liquid sweetener drops here is that adding additional powdered sweetener will make the frosting thinner and more liquid-y in texture, not thick and whipped.

Frost cooled cake with whipped white frosting, or frosting of choice.

Slice, and enjoy!