Preheat oven to 350F degrees. Gather your ingredients so that you have everything close at hand on the counter or table. Coat two baking sheets with butter or baking spray.
Combine Snack Ingredients
In a large roasting pan, combine the Fritos corn chips, the Chex wheat cereal, pretzels, and mix nuts. Set aside.
Make the Candy Coating
In a small saucepan combine the brown sugar, butter, and corn syrup. Cook over medium heat until the butter melts. Stir to combine.
Bring the mixture to a boil, and boil for 4 minutes, without stirring.The sugar coating will reach softball stage with a temperature of 235-240 degrees.
Remove from heat and pour the coating over the Frito mixture. Stir with a long-handled wooden spoon to everything is evenly coated.
Bake uncovered in a preheated oven for 10 minutes. Stir mixture and bake an additional 10 minutes. Remove from oven and stir the mixture once more.
Transfer the hot mixture to the prepared baking sheets. Allow to cool completely, for about 30-40 minutes.
Break into small pieces and sprinkle the mixture with M&M chocolate candies.
Store in a freezer bag or an airtight container for up to 3 weeks. This recipe will make approximately 15 cups and will serve 25 people.
Notes
*Unless otherwise indicated, all butter used on this recipe site is salted.