Preheat your oven to 375 degrees.
In a medium sized skillet, heat olive oil on a medium heat setting. Once warm, add in chopped onion. Allow to caramelize and become golden in color. Stir often to prevent burning.
While your onion is sautéing, combine the flour, baking soda, and salt in a large bowl. Mix well.
Grate your cheese and set aside. After your onion has cooked and is translucent and browned, place with your flour mixture.
Top with the shredded cheese:
Stir to incorporate the onions and cheddar.
Next, make a well in the middle of the flour mixture. Then, slowly pour the Dr Pepper into the mix.
Stir just until the mixture has come together. You don't want to over mix.
Place in a loaf pan that has been greased with non-stick spray or butter.
Bake for 40 minutes. Coat the top with 3 tablespoons melted butter, cover with foil and bake an additional 5 minutes. Make sure your bread is cooked through (a toothpick should come out clean from the center). Cool on a wire rack for 5 minutes, then remove from the loaf pan.
Try to resist eating it while it cools! Your house should smell amazing!