Have the ham and chicken at room temperature for several hours before opening the cans, so that ham will be soft and chicken juice liquid.
Spread the bottom and sides of the pastry shell with ham.
Drain the chicken; chop the meat.
Mix chicken liquid with the eggs, cream, seasonings and onion.
Spread chicken and cheese over the ham and then pour in the egg mixture.
Bake at 425 F for 15 minutes; reduce heat to 350F and bake until centre of filling is set — about 20 minutes.