In a paella pan, add the garlic and sear the hake and prawns. Set them aside.

In the same pan, toast the noodles until lightly golden.

Add the caramelized onion, tomato sauce, and paprika. Stir to combine, then pour in the fish stock. Cook over high heat for 8 minutes.

Add the clams and prawns, then transfer the pan to a preheated oven at 400°F (200°C) for about 6 minutes.

Spread the romesco sauce over the hake and add it to the fideuá. Let it rest in the oven.

Let it sit for 3 to 5 minutes, until the clams have opened.

Serve with extra romesco sauce to taste.