Lightly butter a jelly-roll pan. In a 3-quart microwave-safe casserole with high sides, mix sugar, salt, syrup, and 1 cup hot water. Cook on High until boiling, about 8 minutes. Stir. Cook until mixture reaches 260F on a candy thermometer, about 15 to 20 minutes. When the bubbling stops, stir in 2 tablespoons butter, the vanilla, and food color. Pour into prepared pan. Cool about 5 minutes. Lightly butter hands; gather one sixth of taffy into a ball. Pull until taffy holds its shape in a 1/2-inch thick strand. With buttered shears, cut into 1-inch lengths. Wrap each piece in plastic wrap.

Makes 1 1/2 pounds.