Preheat oven to 375F and place rack to the middle position. Spray a 9-inch pie dish with baking spray. Mince the shallot or onion. Grate the cheese and Snip the chives.

Heat a saute pan over medium heat and when hot, add 2 tbps butter and the sliced mushrooms. Stir to coat the mushrooms. Saute for two minutes.

Then stir and s aute 1-2 minutes more or until some of the moisture has been removed. Transfer to a small plate to cool.

Place the saute pan back onto medium heat and when hot add 1 tbsp butter and the onions. stir to coat and saute until softened, remove from heat.

Add the eggs, heavy cream and water and salt and pepper to a medium bowl, beat at high speed until combined and frothy.

add 1/3 of the cheese to the bottom of the pie dish, spreading it so that it is even. Arrange 1/2 of the onions and mushrooms evenly over the cheese.

Top with the remaining ingredients

bake for 15 min at 375F then for 15 minutes at 350F or until the top is browned and the middle is just set. If may puff up a bit, let cool to room temperature before service or cover and refriderate until needed.