3 cups crisp oat cereal squares
3 cups corn-and-rice cereal
3 cups crisp wheat cereal squares
1 (11.5-ounce) can lightly salted mixed nuts
2 (1-ounce) envelopes Ranch dressing mix
1/2 cup vegetable oil
Stir together all ingredients in a large glass bowl, tossing to coat.
Microwave cereal mixture at HIGH 2 minutes, and stir well. Microwave at HIGH 2 more minutes, and stir. Spread mixture in a single layer on wax paper, and let cool 30 minutes.