Preheat oven to 450F. Melt the bacon fat in a cast iron skillet set over medium heat.
Add the onion and garlic and cook for 3 minutes, until just soft. Add in the tomato paste and cook, stirring for 1-2 minutes or until you can smell it cooking. Add the brown sugar, mustard powder, Worcestershire sauce and salt. Stir and cook for 2-3 minutes.
Add the kidney beans and simmer over low heat for 20-30 minutes, until the beans are soft. Add in the baked beans and potatoes, and stir gently to combine. Cook for a minute just to warm up.
Stir the hot dog pieces into the bean mixture and transfer the skillet to the oven.
Bake for 25 minutes. Serve immediately.
Notes
I serve this with a side of Honey Sweet Corn Bread. It’s my absolute favorite!