This is an appetizer that I know from home, always a self-respecting housewife has 1-2 cans of smoked sprat in the house. And if you need a quick, tasty and good-looking appetizer, such canapés/or sandwiches were made. It is the favorite of many, and no matter how simple it is, it is just as quickly eaten first on the table, even with other more sophisticated dishes there.
Cut the bread into triangles, if it is not very dense in the core, it would be good to dry it a little on a pan.
Grease each slice with mayonnaise or butter.
Place the fish on the longer side of the triangle.
On the opposite side a slice of tomato - here I put half a cherry tomato.
Beautify with greens and red onion slices as desired.
And quickly at the table with them :)
Good appetite!