Stir one-fourth of this mixture into the salmon mixture, then fold in the rest.
Remove salmon mixture from heat and stir in ricotta mixture.
Shape the salmon mixture into small patties about three inches across and roll them in bread crumbs.
Add 2 tablespoons of salmon mixture to each ramekin.
To serve, use the excess plastic wrap to lift the salmon mixture slightly from the container.
Add a third of the whipped cream to the salmon mixture, and fold in gently.
Add tomato, if desired; top with salmon mixture.
Arrange the melba toast rounds on the baking sheet and spoon some of the salmon mixture onto each.
Half fill the dishes with the salmon mixture, then place a teaspoon of caviar in the centre.
Pour half of the salmon mixture into the pan.