Cheesy Ranch Chex Mix

I wanted to make something not sweet for snacking on, so I tried this recipe from the back of a Chex box.

9	cups Corn Chex®, Rice Chex® or Wheat Chex® cereal (or combination)
2	cups bite-size pretzel twists
2	cups bite-size cheese crackers
3	tablespoons butter or margarine, melted
1	package (1 oz) ranch dressing and seasoning mix
1/2	cup grated Parmesan cheese

	In large microwavable bowl, mix cereal, pretzels and crackers. In small microwavable bowl, microwave butter uncovered on High about 30 seconds or until melted. Pour over cereal mixture; stir until evenly coated. Stir in dressing mix and cheese until evenly coated.
	Microwave uncovered on High 3 minutes, stirring after each minute. Spread on waxed paper or foil to cool. Store in airtight container.