01 -
Preheat the oven to 350 degrees F. Spray the inside of a 1 pound (8.5x8.4) loaf pan with baking spray.
02 -
In a small bowl, whisk together 1/3 cup of sugar, chopped walnuts, and the cinnamon.
03 -
In a large bowl, whisk together the flour, the remaining 1 cup sugar, baking powder, and salt.
04 -
In a medium bowl, whisk together the egg, milk, vegetable oil, sour cream, and vanilla extract.
05 -
Add the wet ingredients to the dry and mix until just combined. Batter may be slightly lumpy.
06 -
Add half of the batter to prepared pan. Sprinkle with half of the cinnamon mixture. Top with remaining batter and cinnamon mixture.
07 -
Use a butterknife to make one quick swirl through the batter to give your bread a marbled look.
08 -
Bake for 60 to 67 minutes or until a toothpick inserted near the center comes out clean. Cover with foil halfway through if top browns too quickly.
09 -
Allow the bread to cool completely before slicing to serve.