Great grandma used this exact trick when pennies were tight. Just 4 ingredients for a surprisingly flavorful and warming bowl

When my great-grandma talked about the lean years, she always smiled when she mentioned her cabbage and onion soup. She’d say, “When pennies were tight, you leaned on your onions.” This slow cooker version keeps her same old trick: just cabbage, onions, a good broth, and a bit of fat to coax out every bit of sweetness and flavor. With only four ingredients and a quiet day on the counter, you end up with a surprisingly rich, golden-brown broth, tender ribbons of cabbage, and soft onions that taste like they’ve been cared for all day—because they have.

Ladle this soup into warm bowls and serve with thick slices of crusty bread or simple buttered toast for dipping into the golden broth. A sprinkle of black pepper at the table is all it really needs, but a sharp cheddar sandwich or a grilled cheese on the side turns it into a full supper. It also pairs nicely with a simple green salad or sliced apples for something cool and crisp against the warm, steamy bowl.

Servings: 4

1 medium green cabbage (about 2 to 2 1/2 pounds), cored and thinly sliced

Thinly slice the cabbage into narrow shreds and the onions into thin half-moons so they soften evenly in the slow cooker.

Place the sliced cabbage and onions into the slow cooker, tossing them together with your hands so they’re loosely mixed.

Drizzle the butter or vegetable oil evenly over the cabbage and onions. This small bit of fat is the old-fashioned trick that helps the vegetables turn sweet and gives the broth a rich, golden look.

Pour the broth over the vegetables. Gently press down with a spoon so everything is mostly submerged, but don’t pack it too tightly.

Cover the slow cooker and cook on LOW for 7 to 8 hours, or on HIGH for 3 1/2 to 4 hours, until the cabbage is very tender, the onions are soft and silky, and the broth is a deep golden brown with tiny droplets of fat on top.

Taste the soup and, if desired, add a small pinch of salt or a crack of black pepper at the table, keeping in mind that the broth may already contain salt. Ladle into bowls and serve hot, scooping down to get plenty of the tender cabbage and onions along with the broth.

If you want to stay close to great-grandma’s thrifty style but add a little something extra, you can tuck in one or two simple additions without changing the spirit of the recipe. For a heartier bowl, stir in 1 cup of cooked rice, barley, or small pasta during the last 30 minutes of cooking so it can warm through without getting mushy. A Midwest-style twist is to add a small diced potato or two along with the cabbage and onions; it will break down a bit and make the broth feel creamier. For more depth of flavor, you can briefly soften the onions in a skillet with the butter or oil until they’re lightly golden before adding them to the slow cooker—this echoes the old method of starting soup on the stovetop, but it’s optional. If you have leftover ham bone, a few soup bones, or a smoked sausage end, you can nestle it into the pot with the vegetables and use water instead of broth; it will create its own flavorful stock as it cooks. To keep the recipe strictly vegetarian, use vegetable broth and oil instead of butter. Leftovers keep well in the refrigerator for several days and actually taste richer the next day; reheat gently on the stove or in the microwave, adding a splash of water or broth if the soup has thickened.