Heat olive oil in a deep skillet over medium-high heat. Add onion to pan and cook for 3-4 minutes, until soft. Add garlic to pan and cook for 30 seconds, or until fragrant.
Add beans and liquid to the pan and combine with onions. Bring to a simmer. Turn heat to low and cook at a low simmer for about 9-14 minutes until most of liquid has evaporated.
Mash beans to desired consistency. Season with salt to taste.
