Combine flour baking powder and salt, mixing well.
Combine sugar and butter in a large bowl and mix well (you can use an electric mixer if you wish). Add egg and vanilla. Mix well.
Add flour mixture. Mix well.
Divide dough into four equal parts (or however many colors you want). Add several drops of food coloring to each divided section. Knead until color is throughout. (this will initially dye your hands, but as you knead, the coloring will go back to the dough - wear gloves or use an electric mixer if this stresses you out).
Shape each color into a log and then combine colors to make one large log. Wrap log in saran wrap (to keep from sticking to counter) and roll together (like a snake) until it is the desired cookie cutting diameter (keep in mind, cookies will grow in the oven!).***
Chill in refrigerator for two hours, or until dough is firm.
Preheat oven to 350 degrees.
Slice cookie log (1/4" - 1/2" slices)**** and place slices on lightly greased cookie sheet.
Bake 10-15 minutes (I sliced mine 1/2"; they took 14 minutes and came out perfectly soft and chewy. Mmmmm.)
10. Cool completely (ha!).
Notes
Calories are automatically generated. For best results calculate based on your exact ingredients.