Carmelized Cipolline Onions:
Preheat oven to 375 degrees.
In a medium saucepan bring 2 cups of water to a boil.
Drop the Cipolline onions into the water and wait 1 minute.
Drain the onions.
Slice the root end off of each onion and remove the thin papery skin.
Cut the remaining top off each onion.
Slice each onion in half through the thickest part.
Spray a sheet pan with olive oil and place each half on the oiled sheet, cut side down.
Roast the onions at 375 degrees F. for 20 minutes.
Let the onions cool before using in the quiche.
Slice the roasted baby potatoes and line the bottom of the unbaked pie shell with them.
Sprinkle the bacon bits on top.
Sautee the sliced mushrooms until browned.
When the mushrooms are cooled, place them on top of the bacon in the pie shell.
Sprinkle 1 cup of the grated cheese on top of the mushrooms.
Beat the eggs and milk together.
Pour the eggs and milk into the center of the filled pie shell.
Carefully place the roasted onions on top of the filled quiche, caramelized side up.
Sprinkle the remaining cheese on top.
Reduce the oven temperature to 350 degrees F.
Bake the quiche for 55 - 60 minutes, until it is puffed and golden brown, and a knife inserted in the center comes out clean.
Let it cool and set for at least 10 minutes before serving.