First preheat oven to 350 degrees temperature ( 180 degrees C) and place the oven rack to Middle position. Butter the bottom and sides of a 9 x 5 x 3 inch ( 23 x 13 x 8 cm) Loaf pan. (You can also use a non stick vegetable spray to grease the loaf pan). Line the bottom of the pan with a parchment paper.
In a large bowl whisk together the dry ingredients, the flour, sugar, baking powder, baking soda, salt, and ground cinnamon. Stir in the chopped nuts.
In a medium-sized bowl combine the wet ingredients, mashed bananas, beaten eggs, melted butter, and vanilla. With a rubber spatula or wooden spoon, lightly fold the wet ingredients (banana mixture) into the dry ingredients just until combined and the batter is thick and chunky. (The important thing is not to over mix the batter. You do not want it smooth. Over mixing the batter will tough the bread.)
Pour the batter into prepared pan, smoothing the top with the back of a spoon. Bake until bread is golden brown and a toothpick inserted into the center comes out clean, about 60 to 70 minutes.
Place on a wire rack to cool and then remove the bread from the pan. Serve it warm or at room temperature. This bread can be frozen.
Enjoy it with a delicious butter and a cup of coffee or tea.