Steps
- Chop 1 large onion, 2 celery stalks, 1 leek, and 6 button mushrooms. Soften in a little olive oil for 5 minutes. Add 500g of rinsed tuna bones and skin, 3 parsley stalks, and water to cover.
- Bring to a boil, skim, then simmer for 12 minutes and strain. Meanwhile, peel 1kg of russet potatoes; cut partway through and break into rough 1½in / 4cm chunks.
- Finely chop 2 large red onions, 2 green bell peppers, 1 garlic clove, and 1 scallion. Soften in 2 tablespoons of extra-virgin olive oil in a large pot. Add potatoes and stir over low heat for 5 minutes.
- Add stock to cover and 1 tablespoon of choricero pepper puree; season with salt. Simmer for about 15 minutes, gently shaking the pot occasionally, until the potatoes are tender.
- Cut 500g of boneless fresh tuna into ¾in / 2cm chunks. Add and simmer for 2-3 minutes, then remove from heat and cover for 5 minutes. Finish with chopped parsley.