Catalan almond and pepper sauce (Romesco)

1. Seed the ñora peppers, soak in hot water for 30 minutes and scrape out the flesh with a knife. If you can't get them, use 2 oven-roasted, peeled sweet red peppers and 1 teaspoon smoked paprika. Preheat the oven to 200 °C.

2. Roast the tomatoes and the whole garlic bulb (top cut off) in a tin, drizzled with a little oil, for 25-30 minutes until soft; peel the tomatoes and squeeze the garlic cloves out of their skins.

3. Toast the almonds and hazelnuts in a dry frying pan for 3-4 minutes (rub the skins off the hazelnuts) and fry the slice of bread in a little oil until golden.

4. Coarsely grind the almonds, hazelnuts and bread in a mortar or food processor, then add the pepper flesh, tomatoes and garlic and work into a thick, slightly grainy paste.

5. Gradually work in the olive oil and sherry vinegar until you have a thick, glossy sauce; season with salt.

6. Serve at room temperature with grilled fish, vegetables or spring onions (calçots).

Tip: Romesco shouldn't be completely smooth – the slightly grainy texture is its character, so don't over-blend it.