Preheat your oven to 350°F (175°C) and grease a 9x13 inch baking pan. In a large bowl, whisk together flour, baking soda, cinnamon, ginger, nutmeg, cloves, and salt; set aside.
In a large bowl, cream together butter, sugars, vanilla, and molasses for about 2-3 minutes, or until light and fluffy. Mix in egg until completely combined.
Gradually add the dry ingredients to the wet ingredients, forming a soft dough.
Spread dough evenly into prepared pan. Bake 15-20 minutes, or until darker in color and toothpick inserted comes out with just a few moist crumbs. Move pan to wire rack and cool completely before frosting.
To Make the Frosting: While the bars cool, beat together cream cheese and butter until light and fluffy, 2-3 minutes. Add powdered sugar and vanilla and mix until creamy. Once cooled, spread the cream cheese frosting evenly over the bars and finish by generously sprinkling festive holiday sprinkles.
Allow the frosting to set before cutting the bars into squares and serving.