This simple cheese and potato soup is a staple in Ecuadoran kitchens.
2 tbsp. butter
1 medium onion, finely chopped
1 medium tomato, finely chopped, or 2 tsp. tomato paste
1 1/4 tsp. salt
1/4 tsp. freshly ground black pepper
1/8 tsp. chile or cayenne powder (optional)
1 large bay leaf
3 cups chopped potatoes—half finely chopped and half coarsely chopped
1 cup milk
1 egg, beaten
2 cups grated queso seco, queso duro, queso cotija, or Parmesan cheese
1 avocado, thinly sliced
1. In a large soup pot, melt butter. Add onion, tomato (or tomato paste), salt, black pepper, chile powder, and bay leaf. Cook for 1 minute. Add potatoes and 1 cup water. Simmer covered over medium heat for 25 minutes, stirring occasionally.
2. Add 1 1/2 cups water and cook until the potatoes are tender, about 25 minutes. Measure out 2 cups of the broth and transfer to a bowl to cool slightly. Cover the soup and cook for 5 more minutes.
3. Meanwhile, in a small bowl, lightly beat egg and milk together. Add to it the 2 cups of cooled broth, stirring constantly to prevent curdling. Slowly stir this mixture back into the soup. Stir in the cheese and remove from heat. Let the soup sit covered for 2 to 3 minutes before serving.
4. Top each serving with avocado slices.