1In slow cooker, place both cereals. Add pretzels and corn chips.
2In small bowl, stir together butter, taco and dressing mixes with whisk until well combined. Pour over cereal mixture; stir until evenly coated.
3Cook uncovered on High heat setting 2 hours, stirring every 15 to 20 minutes.
4Spread mixture on cookie sheet or tray; cool 3 to 5 minutes before serving.