Preheat the oven to 350°F. Line a 9-inch square pan with parchment paper.
Press the Pillsbury Candy Cane sugar cookie dough evenly into the bottom of the pan. Sprinkle the baking confetti over the dough and gently press it in so it sticks to the surface.
Bake 12–15 minutes, until the cookie base is lightly golden and set. Allow to cool completely.
In a mixing bowl, beat together the cream cheese, whipped topping, powdered sugar, and vanilla until smooth and fluffy.
Spread the cream layer evenly over the cooled cookie base.
Arrange the baked and cooled Christmas tree sugar cookies on top in neat rows, gently pressing them into the cream layer. Scatter additional baking confetti between cookies for extra color.
Refrigerate for 30–60 minutes until set.
Slice carefully, cutting around each tree so every bar showcases a full cookie design.