1. Preheat the oven to 350°F.
2. Grease a 9 x 5 x 3-inch loaf pan.
3. Combine the flours, baking soda and salt in a medium bowl.
4. Melt the butter in a saucepan over medium heat. Cook, stirring occasionally and scraping the bottom of the pan until it turns a deep golden brown and smells nutty. Be careful not to burn. Cool slightly.
5. In a large bowl, mix the cooled butter, bananas, sugars, yogurt, eggs and vanilla. Stir well.
6. Fold in the flour mixture and stir until just combined.
7. Pour half the batter into the prepared pan and spread it evenly.
8. Dollop the almond butter over the top and use a knife to swirl it into the batter.
9. Sprinkle the brown sugar and cinnamon over the top.
10. Pour the remaining batter over the top.
11. Bake for 50 to 60 minutes or until golden brown and when a toothpick inserted into the center comes out clean.