Homemade mackerel

Remove the head and tail of the mackerel, gut it, and rinse it. Make the marinade (for 4 fish): In 1 liter of water add: -3 tablespoons of salt, -2 tablespoons of sugar, -2 handfuls of onion peels, -2 tablespoons of tea (dry leaves). Bring the brine to a boil, cool it down, and pour it over the mackerel. Place it in the refrigerator for 3 days.