In a small microwavable bowl, combine peanut butter, butter, and spices. Microwave on High 1 minute, or until butter melts. Mix well. In a 13x9 inch baking dish, combine popcorn, shredded wheat and pretzels. Pour peanut butter mixture over popcorn mixture and toss until well coated. Bake at 350 for 30 minutes, stirring halfway through cooking time. Cool popcorn mixture to room temperature, stir in candy pieces. Makes 8 cups. Store in airtight container. Source: