Preheat oven to 250º
Popcorn can be air popped to reduce fat or popped in oil.
Place popped popcorn in a roasting pan. Sprinkle with salt, to taste.
In a small bowl, mix together the white cheddar cheese powder and chili or cayenne powder; set aside.
In a small microwave proof bowl, melt the butter.
Pour the melted butter over the popped corn and stir to coat popcorn.
Immediately pour the cheese mixture over the buttered popcorn, stir to evenly coat popcorn.
Bake at 250º for 30 to 45 minutes, stirring every 15 minutes.
Remove pan from oven and pour popcorn on waxed or parchment paper. Cool.
Store in a resealable airtight container or in plastic resealable baggies.