The Lorann brand strawberry extract is already a red color that will enhance the pink color of your cookie dough. You will not need to add any extra gel food coloring if this is the brand you use. If you use a brand that is clear, then you may want to add a couple of drops of red gel food coloring to deepen the color pink of your cookies. You do not need to add the additional food coloring if you do not wish. The cookies will still be a light pink color from the addition of the strawberry-flavored gelatin powder.