3 tb Plus 1 tsp. vegetable oil
2 1/2 c Chopped onions
8 c Acorn squash; peeled & cut into 1" pieces
2 tb Chopped fresh ginger
4 1/2 c Canned low-salt chicken broth; or more if needed
2 tb Tomato puree
1 pn Cayenne pepper
1 tb Cumin seeds
1 tb Mustard seeds
Heat 3 tablespoons oil in a heavy large pot over medium-high heat. Add onions; saute‚ until light golden, about 8 minutes. Add squash and ginger; sauté‚ 5 minutes. Add 4-1/2 cups broth. Simmer until squash is very tender, about 35 minutes.
Working in batches, puree soup in blender. Return to same pot. Add tomato puree and cayenne. Season to taste with salt and pepper. Simmer 10 minutes to blend flavors, add more broth if soup is too thick. (Can be prepared 1 day ahead. Cover and refrigerate. Re-warm soup over medium heat before serving. )
Heat 1 teaspoon oil in small skillet over medium heat. Add cumin and mustard seeds and stir until fragrant, about 2 minutes. Ladle soup into bowls. Top with seed mixture and serve.
