1Grease 17x12-inch half-sheet pan or 15x10x1-inch pan with butter.
2In large microwavable bowl, mix sugar and corn syrup. Cover with microwavable plastic wrap; microwave on High 4 minutes. Uncover; microwave 7 to 8 minutes or until light golden brown. Stir in nuts, coconut and pineapple. Microwave 1 minute longer or until boiling. Stir in 3 tablespoons butter, the baking soda and vanilla.
3Immediately pour into pan and spread evenly with lightly greased offset spatula. Cool 1 hour or until completely cooled. Break into 2-inch pieces. Store tightly covered at room temperature.