Drain salmon, reserving liquid.
In blender combine salmon liquid, eggs, milk, flour, and salt. Blend until smooth.
Pour into a greased deep 10" pie plate.
Sprinkle salmon, relish, cheeses,and onion on top, pressing in lightly to coat cheese with egg mixture.
Bake @400F 25-35 min until set and golden.
Let stand 5 min before serving.
