Preheat oven to 350 degrees. Line the bottoms of (2) 3 1/2" x 7 1/2" loaf pans with waxed paper. Additionally, spray pans with paper bottoms with nonstick baking spray.
In another mixing bowl, combine the flour, baking soda, baking powder, and salt. Gradually add the dry ingredients to the wet mixture. Stir until batter is combined. Lastly, stir in the chopped nuts. Evenly pour the batter into the prepared pans.
1. For the crumb topping: In a bowl, combined the softened butter, brown sugar and flour. Mix with a fork until crumbly. Sprinkle over the batter of each loaf.
Bake at 350 degrees for 40-45 minutes or until toothpick inserted comes out clean and free of crumbs. Let cook on rack for 10 minutes before removing from pans. Remember to remove the waxed paper from the bottoms. Slice warm or let cool.