Easy Marshmallow Pinwheels

Add warm water to dry gelatin mix in medium microwaveable bowl; stir. Microwave on HIGH 1-1/2 min.; stir until gelatin is completely dissolved.

Stir in marshmallows. Microwave on HIGH 30 sec. to 1 min. or until marshmallows are slightly puffed. Stir with whisk until marshmallows are completely melted and mixture is well blended.

Pour into 9-inch square pan sprayed with cooking spray.

Refrigerate 45 min. or until firm.

Run sharp knife around edges of pan to loosen gelatin from pan. Starting at 1 edge, roll up gelatin layer tightly. Transfer gelatin roll to cutting board, then cut into 1/2-inch-thick slices.