1 tbsp oil
1 cup diced onion
2 cloves garlic minced
2 15 oz pinto beans, drained and rinsed
2 15 oz cans kidney beans, drained and rinsed
2 15 oz cans cannellini beans, drained and rinsed
2 12 oz bottles root beer (like IBC Root Beer)
1/2 cup apple cider vinegar
1/2 cup ketchup
3 tbsp brown sugar
2 tbsp dijon mustard
2 tsp chili powder
1 1/2 tsp kosher salt
1 tsp ground black pepper
Preheat oven to 400f degrees. In a large dutch oven (or other oven-safe pot), heat oil over medium-high heat. Add onion; cook, stirring frequently, until just browned, about 6 minutes. Add garlic and cook for an additional minute.
Stir in beans
Then add all the remaining ingredients.
Bring to a boil.
Transfer the pot (uncovered) to oven and bake for about 45 minutes until liquid thickens.
Stir before serving.