In large bowl, beat 3 cups powdered sugar, the butter, vanilla, 1 teaspoon almond extract and eggs with electric mixer on medium speed, or mix with spoon. Stir in flour, baking soda and cream of tartar. Cover and refrigerate at least 2 hours.
Heat oven to 375 degrees F. Lightly grease cookie sheet. Divide dough in half. On lightly floured surface, roll each half 1/8 inch thick. Cut into desired shapes with 3-inch cookie cutters. Place about 2 inches apart on cookie sheet.
Bake 5 to 7 minutes or until edges are light brown. Remove from cookie sheet to wire rack. Cool completely, about 30 minutes.
In small bowl, beat all glaze ingredients except food colors on low speed until smooth. Divide among several small bowls. Stir desired food color, one drop at a time, into each until desired color. Decorate cookies with glaze and other decorations as desired.