Peanut Butter Banana Frozen Yogurt

makes about  1  1/2 pints

• 4 frozen bananas
• 2 cups Greek yogurt (nonfat is OK)
• 1/2 cup creamy peanut butter
• 1/2 cup whole milk
• 1/4 cup brown sugar
• 1  1/2 teaspoons vanilla

for the peanut butter swirl

• 1/4 cup peanut butter
• 1 tablespoon brown sugar

Mix frozen bananas, yogurt, peanut butter, milk, brown sugar and vanilla in a blender until smooth. Place mixture into a loaf pan and freeze for 1 1/2 hours. Meanwhile make the peanut butter swirl. Place peanut butter and brown sugar in a microwave safe bowl. Heat for 30-40 seconds on HIGH, or until peanut butter is nicely melted and smooth. Drizzle the peanut butter mixture on top of the frozen yogurt and lightly swirl into the frozen yogurt, making marble patterns. Cover the frozen yogurt and freeze for another 3-6 hours, or until firm.