For the noodles: Add the flour, water and salt into a large bowl or food processor and stir together/blitz until a cohesive dough forms. Add 1 tbsp of water at a time if the dough is too dry. Place into a bowl, cover and let rest for 20-25 mins.

Meanwhile, remove the heads and shell from the prawns and set aside. Devein the prawns (optional). Peel and thinly slice the garlic. Trim the spring onion and thinly slice.

Place a saucepan on medium-high heat with 3 tbsps of oil. Once hot, add the prawn heads and shells. Cook, stirring for 4-5 mins until pink and fragrant. Add the garlic, spring onion whites and 2/3 of the gochujang, fry for 1 min until the onion has softened. Pour in 500ml of water, making sure to scrape the bottom of the pan. Bring to a boil, turn the heat down to medium and let simmer for 15-20 mins to infuse the flavours.

Bring a large pot of water to the boil. Sieve the solids out of the sauce and return to medium-high heat. Reduce the sauce by half.

Coat a clean pair of kitchen scissors with some oil. Snip 1cm pieces into the boiling water and cook until they have floated up to the surface, stirring occasionally to prevent sticking. Drain the cooked noodles, making sure to reserve 350ml of noodle cooking water.

Add the raw prawns into the sauce with the remaining gochujang, noodles and some noodle water, cook stirring until the prawns are cooked and the sauce is silky, glossy and coats the noodles. Taste and season with salt, pepper and lime juice.

Share the noodles and prawns into bowls and top with spring onions. Serve with any remaining lime wedges.