Heat the oil in a medium saucepan over medium heat. Add the onion and cook, stirring, until softened, about 5-6 minutes. Add the garlic, chili powder, cumin and oregano and cook for 1 minute, until fragrant.
Add the beans and broth/water and bring to a simmer. Cover, reduce heat to low, and cook for 10 minutes, stirring every few minutes to prevent burning.
Remove the lid, add the lime juice and use a wooden spoon or potato masher to mash the beans to your desired consistency. Season to tase with salt, lime juice and/or adobo sauce for more spice.
Refried beans will last about 5 days in an airtight container in the fridge. Reheat them in the microwave or on the stovetop with a splash of broth to loosen them up a bit.