To prepare this dish we should use large oyster type shells, if these are not available you can use small oven safe dishes. Clay is ones are the best.

Finely dice the mushrooms. Place in a frying pan in oil and sauté until they are done.

Remove from the pan and in the same oil add the flour and stir so it does not lump. allow to simmer lightly and add the salt and pepper..

Add the milk little by little stirring constantly until it begins to thicken.

Add the tuna and the mushrooms and allow to cook 5 minutes.

Divide the mixture between the dishes or shells.

Dust with the grated cheese and put in the oven to melt at a medium temperature. Leave until they brown and sprinkle with the parsley.

The presentation depends on you, as you see in the photo above the decoration is very simple and is very attractive with tomato slices and a piece of mushroom.