Drain pineapple, reserving juice in a 2-cup glass measure. Add enough water to reserved liquid to yield 3/4 cup. Add cornstarch and honey; stir with a wire whisk until smooth.
Microwave cornstarch mixture, uncovered, at HIGH for 2 1/2 to 3 minutes or until thickened and bubbly, stirring after 1 1/2 minutes. Stir in whiskey, and microwave at HIGH for 30 seconds. Stir in pineapple, and microwave at HIGH for 30 seconds.
Serve 1/4 cup sauce over 1/2 cup frozen yogurt.