3 tablespoons vegetable oil
2 tablespoons unsalted butter
1 1/2 pound butternut squash, peeled and cut into 1/2-inch pieces
1 large onion, chopped
1 carrot, chopped
1 celery rib, chopped
2 garlic cloves, minced
2 tablespoons minced peeled ginger
1 tablespoon curry powder (preferably Madras)
1 cup red lentils, picked over and rinsed
2 quarts water
1 teaspoon fresh lemon juice, or to taste
For cilantro oil:
1/2 cup chopped cilantro
1/2 cup vegetable oil
Accompaniment: cooked basmati rice
Heat oil with butter in a large heavy pot over medium heat until foam subsides, then cook squash, onion, carrot, celery, garlic, ginger, and 1 teaspoon salt, stirring occasionally, until vegetables are softened and beginning to brown, 15 to 20 minutes.
Stir in curry powder and 1/4 teaspoon pepper and cook, stirring frequently, 2 minutes.
Add lentils and water and simmer, covered, until lentils are tender, 25 to 40 minutes.
Stir in lemon juice and season with salt and pepper.
Make cilantro oil:
Purée cilantro, oil, and 1/2 teaspoon salt in a blender.
Serve soup drizzled with cilantro oil.
Prepared, tried and tested by: Mona Aumair