Instructions: Bring a pot of water to a boil over high heat. Drain and rinse the mushrooms, then blanch them in the boiling water for 3 minutes. Drain once again.

Place the shrimp heads and shells in a pot with 7 cups water and bring to a gentle boil over medium heat. Reduce the heat to medium-low and simmer until the liquid is reduced by 1 cup, about 30 minutes.

Stain the shrimp stock through a sieve over a pot, pressing the shells to extract any juices. Discard the shells and add the lemongrass, chilies, lime leaves, lime juice, and fish sauce to the stock. Season to taste with salt and pepper and simmer the stock, partially covered, over low heat for 15 minutes.

Add the straw mushrooms and tomato wedges and simmer for an additional 5 minutes. Add the shrimp and cook until opaque, about 2 minutes.

Remove from the heat. Serve hot - in a communal bowl or individual soup bowls - garnished with scallion, mung bean sprouts, holy basil, and Fried Garlic Oil.

This recipe yields 4 to 6 servings.

If you would like to email yourself the recipe for later use, or share the recipe with your friends or family, enter the email addresses below and this recipe will be emailed to you and others as well.