Preheat oven to 275 F / 140 C / gas 1

Spray a large roasting pan with non-stick cooking spray. (The larger the better for less mess when stirring.)

In a medium-size microwave-safe bowl (I use a 4-cup Pyrex measuring cup for ease of drizzling), mix butter, corn syrup, honey, and brown sugar. Cook in the microwave for approximately 2 minutes until butter melts. Stir well to incorporate all ingredients.

Place cereal and nuts into the roasting pan. Drizzle the caramel mixture over the cereal and nuts and mix gently but thoroughly until everything is coated.

Bake for 1 hour, stirring every 15 minutes.

Turn out onto a large waxpaper-covered counter or tabletop. Stir often while it cools.