- 1 tablespoon vegetable oil
- 1 small onion, chopped
- 2 (10 ounce) packages frozen chopped broccoli, thawed
- 2 (10.75 ounce) cans cream of celery soup
- 1 (10.75 ounce) can condensed cream of mushroom soup
- 1 cup shredded American cheese
- 2 (10.75 ounce) cans milk
- Heat vegetable oil in a large pot over medium heat; cook the onion in the hot oil until soft, 5 to 7 minutes.
- Drain as much liquid from the onion as possible. Transfer the drained onion to a slow cooker.
- Place the broccoli, cream of celery soup, cream of mushroom soup, American cheese, and milk into the slow cooker.
- Cook on Low until the broccoli is tender and the flavors meld, 3 to 4 hours.