This is such a tasty, simple recipe; I have used it to sprinkle over sugar cookies, but tend to make it almost exclusively to stir into chamomile tea!
2 c. sugar
Using a citrus zester, remove the zest from all of the lemons. Roughly chop zest; transfer to the bowl of a food processor (or blender) fitted with the blade attachment. Add 1 c. sugar to the zest in the food processor. Pulse until the zest has been finely ground, about 3 minutes. Transfer the ground mixture to a medium-sized bowl. Add the remaining cup of sugar, and toss until evenly mixed. Spread the lemon sugar on a baking sheet, and let sit at room temperature until dry, about 1 hour. Store the sugar in an airtight container in a cool, dry place up to 1 month.