Otis Spunkmeyer Muffins Banana Nut Muffins. Shipped frozen, arrive thawed. Otis Spunkmeyer Muffins Banana Nut Muffins. Made with ripe bananas and crunchy walnuts. Individually wrapped for the convenience of people on the go. They are a perfect breakfast, snack or anytime treat. Moist, crumbly and delicious, consumers find Otis Spunkmeyer muffins simply irresistible.