In a food processor blend tuna, sweetcorn, mayonnaise, sour cream, hard-boiled eggs, salt and pepper. Process until smooth.
Wash and finely chop parsley.
On a serving tray (or a square cake board) layer 4 slices of toast bread to create a square (Trim off the crust if you can’t buy “crustless” bread).
Spread a few (3-4) heaped table spoons of the tuna mix over the bread and spread around evenly. Sprinkle some parsley over the spread and cover with bread. Repeat the process until you have used all bread slices (and used all the tuna mix).
Keep it in the fridge for several hours (at least 2 but for best results overnight).
The following day, mix sour cream with mayonnaise and cover the “cake” using a spatula. Sprinkle with grated cheese and chopped spring onion (the green parts only).
Thinly slice the cucumber and tomatoes. Decorate the sides of your cake with these and some dill sprigs. You can put more decorations (lemon slices, cucumber slices = simply cut each slice in half leaving ⅓ uncut. Then grab the 2 cut parts and twist opposite ways – check out video to see how to do it)
If you want it to look really fancy, make little roses from small tomatoes (check out our video to see how to make tomato roses) and place them in each corner.
Keep in the fridge prior to serving!