In a 3-quart slow cooker, combine the cheese crackers, corn cereal, walnuts, and peanuts.
Toss to mix.
In a small saucepan, melt the butter over medium heat.
Remove from heat and stir in Worcestershire sauce, onion salt, and pepper.
Drizzle the mixture over the snack mix in the slow cooker and stir gently to coat.
Cover and cook on low for 2 hours.
After 2 hours, uncover the slow cooker and cook for another hour, stirring occasionally.
Sprinkle the Romano cheese over the mixture, turn the heat to high, and cook for 15–20 more minutes, stirring once during the cooking time.
Spread the snack mix on a cookie sheet to cool.
Store in an airtight container.
Notes / Tips / Wine Advice:
Serving Tip:Serve the snack mix in small bowls, replacing them every hour to keep it fresh and crisp.Wine Advice:Pair with a light, refreshing beer or a dry white wine like Sauvignon Blanc to balance the savory flavors.