Have you heard of the Melva?
Related to the tuna, this pink-fleshed fish is an abundant species on the Costa Andaluza (from Málaga to Huelva).
This product is made with Melva, olive oil, and salt. Store it out of sunlight and once opened, keep in the fridge for up to 5 days. It will keep unopened for 5 years.
Per 100g, the product has 182.8 kcal and 30.4g of protein. It is also low in saturated fat.