Instead of going and buying expensive canned sardines, you will do very simple custom that is much tastier than the canned.

Herring sardines in tomato sauce
1,000 g of herring, small
100 ml of oil
2 tablespoons vinegar
2 tsp salt
0.5 tsp caster sugar
2 pinches of black pepper, ground
0.5 tsp cayenne pepper
4 tbsp tomato puree
1 teaspoon dried coriander
0.5 tsp cumin
1 crushed garlic clove
Rinse the herring. Take off the head and cut off the fins but let’s back leg remain. Add the fish close together with their backs up in an ovenproof dish. Preheat oven to 200 °. Whisk together oil, vinegar, salt, sugar, black pepper, cayenne pepper, garlic, coriander, cumin and tomato paste. Pour the mixture over the herring. Cover pan with foil. Boil the herring in the middle of the oven for 15-20 minutes. Let cool herring covered in mold.