Preheat oven to 350°.
Combine first 4 ingredients (including fudge packet from mix), stirring well. Spread into an 8-inch square baking pan coated with cooking spray. Bake at 350° for 30 minutes or until a wooden pick inserted near edge of pan comes out clean. Cool in pan on a wire rack.
Crumble brownies; place in a food processor. Add bourbon; process until mixture forms a ball (about 30 seconds).
Shape brownie mixture into 24 balls, about 1 1/2 tablespoons each. Place nuts in a shallow bowl. Roll balls in nuts, pressing gently to coat.
Note: Store balls in an airtight container at room temperature for up to three days.