- Whisk butter and sugars in a small bowl until fluffy. Add egg and vanilla, beat. Combine dry ingredients of flour, cream of tartar, salt and baking soda and add gradually to creamed contents, mix completely. Cover with plastic wrap and refrigerate for an hour.
- Roll out 1 inch balls and place 2 inches apart on an ungreased baking tray. Press flat with a sugar coated glass and liberally sprinkle with sprinkles, nuts or colored sugar, toasted coconut.
- Bake cookies at 350°F for 10 to 12 minutes till light brown. Cool on wire racks. Recipe produces 4 dozen butter cookies.