In a medium saucepan, melt 1 tbsp. of the butter over med-high heat. Once its melted, add the onion and jalapeno (if using). Cook, stirring often, until they're softened, about 5 minutes. Then stir in the garlic and cook until it's fragrant.
Stir in the beans, broth, chili powder, cumin and oregano and let this mixture come up to a simmer. Once it begins to bubble, let it simmer for about 5 or so minutes, then remove the pan from the heat. Either use a masher to roughly mash the beans, or use a food processor for a smoother consistency.
Once the beans are mashed, season with the lime juice, salt and pepper. Then stir in the additional tbsp. of butter until it's all melted and incorporated in. That's it! Serve it up with some yummy toppings.
