Cut the lobster into good sized pieces.
Wash the shrimp, do not shell, and cook them in 1/2 cup (125 ml) water for 5 minutes.
Save the strained broth.
Poach the scallops in it for'2 minutes.
Peel the shrimp.
Cook the onions in a little water until just done, drain and add this liquid to the shrimp broth.
This should make 1 1/2 cups.
Make the cream sauce of the butter, flour and all the seasonings, broth and cream.
Arrange the fish in a big pie dish with the onions and add the sauce.
Cover with pastry, made in the next step.
Cut the butter into the flour sifted with the salt and baking powder.
Add just enough water and milk .to wet it so it can be rolled and can cover the pie dish.Make incisions in the pastry to allow the steam to escape.