On a large cookie sheet, spread out your popcorn. Sprinkle with crushed sugar cookie.
In microwaveable bowl, microwave white chocolate and marshmallows, stirring every 20 seconds until melted (avoid scorching).
Drizzle white chocolate mixture over popcorn.
Using spatula, carefully fold popcorn until coated.
If necessary, bake at 350 degrees for 5-7 minutes to remelt chocolate. Fold popcorn until coated.
Allow to cool completely. Break into edible pieces. Store in air tight container.