The first potato soup I ever tasted was bright orange, thanks to a generous amount of Velveeta. It was a soup of its era (the 90s), made by my mother in her slow cooker. At the tender age of five, it made quite an impression on me. From most of my young life, I assumed potato soup had to have a dairy component—heavy cream, cheese, milk, sour cream—but that isn’t true at all. You only need three things to make a creamy vegetable soup: fat, vegetables and liquid.

Don’t believe me? Give our Garnish-as-You-Like Potato-Leek Soup a spin. (And watch Rosemary Gill make it on Instagram.)

It’s creamy, yet cream-less, made with nothing more than potatoes, garlic, leeks, butter and water, plus some seasonings and spices. (If you need to avoid dairy entirely, know that I made it for a vegan friend with some fancy “plant butter” margarine and it turned out great.) It’s the vegetables that do the heavy lifting.

Potato starch and pectin are the real heroes

If you’ve ever used a roux as the base for a creamy béchamel, or swirled a cornstarch slurry into a gravy, you have observed the thickening power of starch. Root starches, like those found in potatoes, are particularly fast-acting and effective. The starch granules in potatoes are very large and its molecules are very long. Those long molecules get all tangled up with each other, thickening soups and sauces quickly while giving them a glossy-smooth appearance.

Leeks also lend body to this silky soup. They’re high in pectin, a long-chain starch that gives the vegetable its prized melty texture. If you do any canning, you’ve seen pectin’s gelling abilities in action. Leeks, combined with starchy potatoes, make a soup that feels creamy and luscious on the tongue, no dairy needed.

A whole head of garlic gives this soup savory sweetness

This is a soup for the garlic heads, in that it contains a whole head of garlic, but the flavor is surprisingly mellow—as is the prep.

Instead of peeling each individual clove, we simply lop off the top, then stick the whole head into the pot. The garlic simmers with the rest of the vegetables until sweet and soft. All you have to do is fish it out and squeeze the cloves into the soup with a pair of tongs. They slide out with surprisingly little force.

Clean the leeks with care

Did you know that leeks are buried with soil as they grow, to increase the amount of pale green and white parts you get per leek? This makes them quite delicious, but very dirty, so the usual rinse-and-go approach will not do.

They’re not hard to clean, however. Just halve them lengthwise, slice them thinly and rinse them vigorously in a bowl of water, emptying and refilling the bowl until no grit remains. Drain them in a colander before adding to the pot.

The soup that helps me clean out my fridge

This soup gets along with everyone, from crispy bacon lardon to pickled onions and toasted nuts. Got a spoonful of sour cream? Dollop it on the soup. A small handful of mushrooms you need to use up? Roast them until they’re nice and crispy, then toss them in the soup. An almost-empty jar of pesto? Scoop it out and drizzle it on the soup. The same goes for pickled vegetables, any cheese you have in your fridge and whatever herbs you have hiding out in your produce drawer.

If you’re feeding a crowd, raid the fridge for garnishes and set them out, buffet-style, and let everyone garnish as they please. Serve with crusty bread for cleaning out the bowls.

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Claire Lower

Claire Lower is the Digital Editor for Christopher Kimball’s Milk Street, with over a decade of experience as a food writer and recipe developer. Claire began writing about food (and drinks) during the blogging boom in the late 2000s, eventually leaving her job as a lab technician to pursue writing full-time. After freelancing for publications such as Serious Eats, Yahoo Food, xoJane and Cherry Bombe Magazine, she eventually landed at Lifehacker, where she served as the Senior Food Editor for nearly eight years. Claire lives in Portland, Oregon with a very friendly dog and very mean cat. When not in the kitchen (or at her laptop), you can find her deadlifting at the gym, fly fishing or trying to master figure drawing at her local art studio.