Prebake the pie shell for 10 minutes in a 400° oven. This is optional but I would suggest doing this. So, if you pre bake crust, make sure you line crust with foil or parchment and weight down with either dried beans, rice, or pie weights.
Fry the bacon until crisp. Drain and set aside. Fry the ham for 3-4 minutes just enough to release the water in the ham.
Beat the eggs with the cream. Add in the green onions, crumbled bacon, mushrooms, ham, cheese, garlic and spices.
Pour into the pre baked pie shell and bake in 350° oven for 35 minutes or until a knife inserted in the center comes out clean. (sometimes mine takes almost an hour. I think it all depends on how cold the ingredients are.)
*Note: I sometimes make this in advance, bake and refrigerate and reheat the next day in a 350° oven until warm. I usually don't pre bake the crust as the original recipe calls for; I just press into pan, pour in the filling and bake.