Chillies, garlic, tamarind paste, fish sauce, sugar, ginger and fish stock in a preheated large wok form. Roughly shred the kaffir lime leaves and add. Bring everything to a boil, stirring throughout.
Reduce the temperature, add the carrots, sweet potatoes and hominy.
Cover and gently simmer soup for 10 min until vegetables are al dente.
Add cilantro, cherry tomatoes and crab tails and steep for 5 min.
Divide the finished soup evenly among preheated bowls and bring to the table hot.