In a skillet, heat the olive oil over medium heat. Add the chopped onion and sauté until translucent, about 5 minutes.

Add the minced garlic and cumin, and cook for another minute until fragrant.

Stir in the cooked beans and salt, mashing them with a potato masher while mixing with the onion and garlic.

Add the vegetable broth gradually, continuing to mash and stir until the beans reach your desired consistency.

Cook for an additional 5-10 minutes, stirring occasionally, until heated through.

Serve warm, topped with cheddar cheese if desired.