Heat the oil in a medium saucepan and saute the shallots, ginger root and chiles over moderate heat, stirring constantly for three minutes.

Add the stock, coconut milk, lemongrass, fish sauce, pumpkin puree and sugar.

Bring to a simmer, then cook, uncovered over low heat, stirring occasionally for about 10 minutes.

Stir in the lime juice and cilantro.

Salt and pepper to taste.

Serve immediately and sprinkle with the peanuts and scallions.