For sandwiches with sprats, we need a sliced loaf. Fry slices of bread in a dry frying pan, on each side until golden brown.
Cut the onion into half rings and marinate in vinegar for 5 minutes, then drain the vinegar.
Mix 5 tablespoon. mayonnaise and 6 tablespoon. ketchup.
Then cut the tomato into half rings. Open a can of sprats. If the sprats are large, cut them in half.
When all the ingredients are ready, we begin to shape the sandwiches. We take a slice of bread, grease it with a mixture of ketchup and mayonnaise, lay on top one sprat, a slice of tomato, and pickled onion.
Put the sandwiches with sprats and vegetables on a dish. Optionally, sandwiches can be decorated with herbs.