Preheat oven to 350°F and line a 9x13 glass baking pan with parchment paper.
Using a hand mixer or electric mixer, cream together butter and sugar. Mix in egg and vanilla extract. Add in flour, baking powder and salt and mix until dough-like.
Spread evenly across the bottom of the baking pan. Bake for 18-23 minutes or until edges are golden brown. Let cool completely.
While cooling, make the cream cheese frosting. Cream together cream cheese and butter, then mix in vanilla extract and red food coloring (optional). Mix in 1/2 cup powdered sugar at a time.
Spread cream cheese frosting evenly across cookie. Top with sprinkles. Cut into 18-24 bars.