Step 1: Combine the beef, ginger, onion, garlic, chilies, curry powder, turmeric, sugar, pepper, and 1 tsp of the salt.
Step 2: Cover and leave to marinate for 2 hours, or overnight in the refrigerator. Heat the oil in a large, heavy-bottomed saucepan and high heat.
Step 3: Add the marinated beef and stir quickly to seal, about 3 minutes. Add 750ml / 1.25 pints hot water, the fish sauce, and the remaining 1 teaspoon salt.
Step 4: Bring to the boil, reduce the heat, cover and simmer until the beef is almost tender, about 1 hour.
Step 5: Add the carrots and simmer, stirring occasionally, for a further 15 minutes. Dissolve the cornflour in the coconut milk and stir the mixture into the stew.
Step 6: Continue simmering, uncovered, stirring to prevent sticking, until the sauce thickens slightly, about 15 minutes.
Step 7: Ladle the curry into a soup tureen and serve immediately.