Combine sugar, water (or canned milk), salt, and corn syrup in a 2 qt. bowl. Bring to a boil in microwave on high (about 3 minutes). Stir and add peanuts. Return to microwave and cook another 8 minutes on high. Remove and add butter, vanilla, and food coloring. Stir until cool and creamy. Drop by teaspoonfuls onto waxed paper.