Line baking sheets with waxed paper; set aside. Combine popcorn and nuts in a large roasting pan. Bake at 250° for 10-15 minutes or until warm. Meanwhile, grease the sides of a heavy saucepan with 1-1/2 teaspoons butter. Combine the sugar, honey and corn syrup in saucepan. Bring to a boil over medium heat, stirring constantly. Boil for 2 minutes without stirring.
Remove from the heat; stir in peanut butter, vanilla and molasses. Pour over warm popcorn mixture and stir to coat. Working quickly, use buttered hands to form mixture into 1-1/2-in. clusters. Place on prepared baking sheets to dry. Store in an airtight container at room temperature. Yield: about 12 dozen.