This South American soup holds many good and tasty things, from the tender pieces of potato to sweet nibbles of fresh corn. But let's be real: the best part is the cheese. Queso fresco to be exact, which doesn't fully melt but rather softens into chewy morsels in the warmth of the milky broth. So good.
Almost every South American country that touches the Andes Mountains has their own particular version of locro. Most start with a base of potatoes and cheese in milky broth, and then add other seasonal or local vegetables as available. Most are also vegetarian, though tender slow-cooked pork is a locro staple in Argentina. Come cooler weather, I'll be adding butternut squash or pumpkin to my locro, as they do in Peru.
The spices and seasoning stay fairly consistent from version to version, often just salt, freshly ground black pepper, and oregano. Spicier versions that I've come across include aji amarillo chiles either cooked right into the soup itself or made into a sauce to spoon on top. If you can't find aji chiles but still want some heat, a pinch of dried chile flakes or cayenne pepper does the job nicely.
I love a chunky soup, so I leave all the vegetables in bite-sized pieces. For something more rib-sticking on a cold night, try smashing the potatoes with the back of a spoon after they've simmered a while, or go all the way and puree the potato soup base before adding the cheese and other vegetables.
And the cheese! Be sure to get queso fresco or another fresh farmer's cheese. It is mild, creamy, salty, and just perfect in this soup. Finding a soft bite of cheese amidst the other vegetables on your spoon is like a surprise and very welcome guest arriving at the party. Locro wouldn't be locro without it.
Andean Cheese & Potato Soup (Locro de Papa)
Serves 6 to 8
For a spicy kick, serve this soup with aji chili sauce. Better yet, add a spoonful along with the garlic and oregano to the soup itself!
Warm a teaspoon or two of olive oil in a large pot (at least 5 quarts) over medium-high heat. Add the onion and cook until translucent and just starting to turn golden-brown, 5 to 8 minutes. Add the potatoes and 1/4 teaspoon salt, and cook until the edges of the potatoes are beginning to soften, another 5 minutes.
Clear a space in the middle of the pan and add the garlic, oregano, and cayenne. Cook until the garlic is fragrant, about 30 seconds, then stir into the onions and potatoes. Add the stock to the pan and bring to a boil. Reduce heat to medium-low, and simmer the soup until the potatoes are tender, 10 to 15 minutes.
Add the corn kernels, peas, queso fresco, and milk to the soup. Bring back to a simmer (do not boil) and cook until the corn and peas are tender, another 5 minutes. Taste and add salt and pepper as needed.
This soup will keep refrigerated for a week. If freezing, remove the portion of soup to be frozen before adding the milk.