Chex Patio Mix

This was on the box of Chex cereals in the 1970's.

6 T. Butter
2 1/2 t. Soy Sauce
1 t. Seasoned Salt
1/4 t. Onion Powder
2 c. Corn Chex
2 c. Rice Chex
2 c. Wheat Chex
1 c. Pretzel Sticks
1 c. Mixed Nuts
Melt butter in microwave, add soy sauce, seasoned salt and onion powder.
Put cereals, pretzels and nuts in large roasting pan, cover with butter and seasonings, mix well.
Heat oven to 250*, cook for 1 hour stirring every 15 minutes.
Drain and cool on paper towels.