A depression era staple my great aunt made to keep nine siblings fed. It uses exactly 4 ingredients to create a rich bowl that is simple, completely filling, and more comforting than people expect.

This 4-ingredient potato soup is the kind of thing our grandmothers leaned on when the money ran thin but the table still had to be full. My great aunt used to make a big pot of it to stretch one sack of potatoes across nine hungry kids during the Depression. It’s nothing fancy—just potatoes, milk, butter, and salt—but those four ingredients come together into a rich, milky broth with soft chunks of potato and little golden pools of melted butter on top. It’s the sort of simple, honest food that fills you up, warms you through, and somehow comforts you more than you expect.

Serve this soup piping hot in sturdy bowls with a thick slice of bread, a biscuit, or a simple piece of toast for dipping into the creamy broth and butter. A side of sliced apples or a small green salad makes a nice fresh contrast if you have it, but this soup is meant to stand on its own when the pantry is bare. For an old-fashioned supper, pair it with a jar of home-canned pickles or beets and a cup of hot tea or coffee.

Servings: 4

2 pounds russet or other starchy potatoes, peeled and cut into 1/2-inch dice

Peel the potatoes and cut them into small, even 1/2-inch cubes so they cook quickly and soften evenly in the soup.

Place the diced potatoes in a medium to large heavy-bottomed pot and pour in just enough water to barely cover them (do not add too much; you want a starchy base, not a thin broth).

Add 1 teaspoon of the salt to the pot. Bring the potatoes to a gentle boil over medium heat, then reduce the heat to medium-low and simmer uncovered until the potatoes are very tender and starting to break at the edges, about 12–15 minutes. Stir occasionally to keep them from sticking.

When the potatoes are soft and the cooking water has turned cloudy and slightly thick, use a spoon or potato masher to lightly mash some of the potatoes right in the pot, leaving plenty of chunks for texture. Do not drain; that starchy water helps thicken the soup.

Pour in the milk and add the butter. Stir gently and cook over low heat until the milk is hot and steamy and the butter is fully melted, 5–8 minutes. Do not let the soup boil hard; keep it just below a simmer to prevent the milk from curdling or scorching on the bottom.

Taste the soup and add the remaining 1/2 teaspoon salt, or more if needed, stirring well. The flavor should be pleasantly salty and buttery, with a naturally sweet taste from the milk and potatoes.

Ladle the soup into warm bowls. If you like, dot the top of each bowl with a small extra pat of butter so it melts into little yellow pools on the surface. Serve immediately while very hot.

To keep the spirit of this Depression-era soup, the base should stay simple, but you can adjust it to your kitchen. If you only have 2% milk, the soup will be a bit lighter; you can simmer it a few minutes longer to thicken slightly, stirring often. If you have only unsalted butter, simply add a pinch more salt at the end. For a thicker, stew-like bowl, mash more of the potatoes before adding the milk, or let the soup sit off the heat for 10 minutes to thicken before serving. For a thinner soup, add a splash more milk. Use a heavy pot and low heat once the milk is added to avoid scorching; stir the bottom gently every few minutes. Food safety tips: Keep the soup hot (above 140°F/60°C) if holding it on the stove, and refrigerate leftovers within 2 hours in shallow containers. Reheat gently over low heat, stirring often, and avoid boiling to keep the milk from separating. Leftovers are best within 2 days. While it’s tempting to leave a pot of this on the back of the stove all afternoon like our elders did, for safety it should be cooled and refrigerated if it won’t be eaten soon.