Whole Wheat Peanut Butter Banana Bread

1. Set oven to 350ºF. Grease and flour two loaf pans and set aside.
2. In a medium bowl, sift together the flour, baking soda, cinnamon, spices, and salt.
3. In a large bowl, beat sugars and eggs with a whisk until light and fluffy, about 10 minutes. Gently pour in oil and mix until well combined.
4. In a small bowl, mix together peanut butter, mashed bananas, yogurt, and vanilla and stir well to incorporate. Add to the sugar and egg mixture.
5. Fold in the dry ingredients, stirring in swift strokes ensuring not to overmix. Pour batter evenly among two pans.
6. For the topping, in a small bowl, mix the brown sugar, flour, and oats. Slowly pour in the melted butter and stir until mixture has the consistency of wet sand. Sprinkle evenly over the loaves.
7. Bake at 350ºF for about 1 hour, until a toothpick inserted in the middle comes out clean.