Heat the oil or bacon fat in a saucepan over medium heat.
Add the onion and cook until soft and lightly golden (5–7 minutes).
Add garlic and cook 30 seconds.
Add cumin, paprika, oregano, and chili powder.
Stir for 20–30 seconds until fragrant—this gives the restaurant-depth.
Pour in the canned pinto beans with their liquid.
Add the broth and bay leaf.
Stir, then bring to a low simmer.
Let the beans gently bubble, uncovered, until slightly thickened and creamy.
Remove bay leaf.
Stir in 1–2 tablespoons of butter for gloss and richness.
Taste and adjust salt.
Lightly mash ¼ of the beans directly in the pot to make them creamier.
