Tom Yam Goong

• 6 thai chiles
• 4 kaffir lime leaves
• 2 stalks lemon grass
• 1 1/2 lengths
• 1 firm tomato
• 950 ml water
• 120 gr shrimp
• 45 ml lime juice
• 45 ml fish sauce
• 45 gr straw mushrooms (canned)