Preheat the oven to 350F° and lightly spray a 9x5-inch baking pan with nonstick cooking spray.
In a large bowl, whisk together the flour, baking soda, salt, and cinnamon. Set aside.
In another large bowl, stir together the sweet potatoes, peanut butter, eggs, butter, brown sugar, and vanilla. Mix well.
Add the dry ingredients to the wet and mix until just combined, being cautious to not over mix. Pour the batter into the prepared pan and sprinkle the chopped peanuts over the batter. Bake for 50 to 60 minutes until a toothpick inserted in the center comes out clean. Allow the bread to cool in the pan for about 10 minutes before removing.
