Sugar Cookie Bars

1 cup butter; room temp.2 cups sugar4 eggs2 tsp vanilla5 cups flour1 tsp salt1/2 tsp soda
Cream butter and sugar until fluffy. Add eggs, one at a time, mixing after each egg. Add vanilla & mix well. In a separate bowl combine flour, salt & soda & stir with a whisk to combine. Add to wet mixture and mix just until combined. Spread on a greased baking sheet (use a 13 x 18 pan). Bake at 375 degrees for 10-15 min, until light golden brown or until a toothpick comes out clean. Cool completely and frost.
Frosting
1/2 cup butter; room temp1/2 cup shortening1 tsp vanillapinch of salt4 cups powdered sugar5 Tbsp milkfood coloring (if desired)
For frosting combine butter and shortening until smooth and creamy. Add vanilla and salt. Add powdered sugar in 1-2 cup increments until combined, then add milk & mix until smooth and spreading consistency. Spread over cooled cookie.