Rainbow Butter Cookies
["1 c. butter", "1 1/2 c. sugar", "1 egg", "1 tsp. vanilla", "2 1/2 c. flour", "1 tsp. baking soda", "1 tsp. cream of tartar", "1/4 tsp. salt", "red, green and yellow food coloring"]
["Cream butter and sugar.", "Blend in egg and vanilla.", "Add dry ingredients, which have been sifted together.", "Mix well.", "Divide dough in 3 parts and tint each part with a different color.", "Drop by teaspoon onto buttered cookie sheet.", "Bake 8 minutes at 375\u00b0. Makes 4 dozen."]
["butter", "sugar", "egg", "vanilla", "flour", "baking soda", "cream of tartar", "salt", "red"]