Microwave popcorn according to package directions. Remove any unpopped kernels.
Spray large (4-quart) microwave-safe bowl with cooking spray. Add Parkay and marshmallows; toss to coat. Microwave on HIGH 1-1/2 minutes or until marshmallows are melted, stirring after 45 seconds. Stir in food color.
Add popped corn; stir gently until coated well. Cool 10 minutes or until popcorn mixture is easy to handle. Moisten hands with water; shape 1/4-cup mixture into 1-1/2-inch balls. Decorate with sprinkles, if desired.