About 2 hours before serving, preheat oven to 250 degrees Fahrenheit. Place popped corn, pecans, and walnuts in large open roasting pan (17 1/4x11 1/2-inches). Set aside.
Prepare caramel coating: In heavy 2-quart saucepan over medium heat, add brown sugar, butter or margarine, corn syrup, and salt to boiling. Boil 5 minutes, stirring frequently. Remove saucepan from heat and stir in vanilla extract.
Spoon caramel-covered popcorn mixture into another large roasting pan or onto waxed paper to cool, stirring occasionally to separate. Store popcorn mixture in tightly covered containers to use within 1 week. Makes approximately 21 cups at 220 calories per cup.
Contributor: Wabash Valley Farms