Toast the Chillies and Veg: Place a dry, heavy-based frying pan over a medium heat. Add the de-stemmed and de-seeded guajillo and ancho chillies. Toast them for about 30-60 seconds per side, pressing down with a spatula, until they become fragrant and slightly change colour. Be careful not to burn them, or the broth will be bitter. Remove the chillies and set them aside. In the same pan, add the halved tomatoes, onion, and garlic. Dry-roast for 5-7 minutes, turning occasionally, until they are softened and have some charred spots.

Soak the Chillies: Place the toasted chillies in a heatproof bowl and cover them with boiling water. Let them soak for 20 minutes until they are completely soft and rehydrated.

Prepare the Prawns: While the chillies are soaking, peel the prawns. Place the prawn meat in a bowl, cover, and refrigerate. Keep the shells and heads – this is where the flavour is!

Make the Prawn Stock: Heat the 1 tbsp of oil in a large saucepan or stockpot over a medium-high heat. Add the prawn shells and heads and cook, stirring frequently, for 3-4 minutes until they turn bright pink and smell aromatic. Pour in the 1.5 litres of water, bring to a simmer, then reduce the heat and let it gently bubble away for 15 minutes.

Blend the Broth Base: Drain the rehydrated chillies, discarding the soaking water. Add them to a blender along with the roasted tomatoes, onion, garlic, cumin seeds, and oregano. Strain about 250ml of the hot prawn stock into the blender. Blend on high for 1-2 minutes until you have a completely smooth purée. I find that using a powerful blender here is key to getting a non-gritty texture.

Combine and Simmer: Strain the remaining prawn stock through a fine-mesh sieve into a clean bowl, pressing down on the shells to extract all the liquid. Discard the shells. Pour the stock back into the pot. Now, pour the blended chilli mixture through the same sieve into the stock. Use the back of a spoon to push all the liquid through, leaving any tough skins or seeds behind.

Cook the Vegetables: Bring the strained broth to a simmer over a medium heat. Add the diced carrots and potatoes, along with the salt and pepper. Let the soup simmer gently for 15-20 minutes, or until the vegetables are tender.

Cook the Prawns: Add the peeled raw prawns to the pot. They will cook very quickly. Simmer for just 2-3 minutes, until they are pink and opaque. Be careful not to overcook them, or they will become tough. Taste the broth and adjust the seasoning with more salt if needed.

Serve: Ladle the hot Caldo de Camaron into bowls. Garnish generously with fresh chopped coriander and serve immediately with lime wedges on the side for squeezing over.