Heat oven to 300 F. Spread popcorn and corn chips in a shallow baking pan lined with foil. Melt butter in small pan. Stir in Mexican seasoning. Pour over popcorn mixture and toss well. Sprinkle with cheese and toss to mix. Bake 5 to 7 minutes until cheese is melted. Serve at once. Makes about 3 1/2 quarts. Just right for two!!!