There are lots of colors and combinations you can do with these! Circles inside of circles, checkerboards, swirly pinwheels or what I call "Beach Balls". With dough in the freezer, I sliced and baked all of these, AND "glued" on the M&Ms before my 9:30 client.
2 1/2 c. flour
1/2 t. baking soda
1/4 t. salt
1 cup unsalted butter, softened
1 1/4 c. sifted powdered sugar
1/4 c. plus 2 T. granulated sugar
1 large egg
3/4 t. vanilla (increase to 1 1/2 t. if you do not add other flavorings)
additional flavorings (almond, lemon, mint...)
gel food colorings
Stir together flour, baking soda and salt in a bowl. Set aside. Stir together butter and sugars in mixer bowl. Beat 1 minute. Add egg, vanilla, and other flavoring, beating until smooth. Add flour mixture, a little at a time, mixing until incorporated.
Divide dough into halves or thirds for 3 colors. Knead in food coloring. Chill dough for 1-2 hours. Form logs, as close to the same size as possible. Wrap, and chill until ready to use.
Slice logs into 6ths. Switch sections, alternating colors. Re-wrap and freeze until ready to use.
Pre-heat oven to 374. Slice and bake 8 minutes. Transfer to wire rack and cool. "Glue on" an M&M of contrasting color in center, using icing or frosting.