Preheat oven to 375 F. Grease two 4 1/2 by 8 1/2-inch loaf pans.
Combine dry ingredients in a small bowl. Beat together the peanut butter, sugar, and oil with an electric mixer until smooth. Beat in the egg or egg substitute. Then, whisk in the milk by hand, carefully, so you don't splatter. Stir in the vanilla.
Pour the dry ingredients into the wet and fold to combine. Stir in chocolate chips and 1/2 cup nuts and pour the batter into the two prepared pans. Sprinkle evenly with remaining nuts.