Rock Candy
["6 c. sugar", "3 c. water", "3/4 tsp. cream of tartar", "food coloring (optional)"]
["Mix it all up in a pot (don't stir).", "Boil until it's 290\u00b0 on the candy thermometer.", "Pour into a square pan thinly and let it cool until hard.", "After it cools, crack and eat.", "I hope you enjoy it."]
["sugar", "water", "cream of tartar", "food coloring"]