Preheat the oven to 360F / 180c.
Add the oil and butter to a skillet and place on a medium high heat. Once hot, add in the sliced mushrooms.
1 tablespoon oil, 1 tablespoon butter, 1½ pounds fresh mushrooms
Once browned, stir in the garlic, onion, thyme salt and pepper. Cook til the onion is softened.
2 garlic cloves, 1 onion, 1 tablespoon dried thyme, ½ teaspoon salt, ¼ teaspoon black pepper
A handful at a time, stir in the spinach to wilt it. Once all of the spinach is cooked, take off of the heat.
5 ounces baby spinach
In a jug, mix together the alfredo sauce and the cream.
14 ounces alfredo sauce, 1 cup cream (35%)
Layer the sliced potatoes in the casserole dish. Sprinkle a little salt and pepper on each layer.
1½ pounds potatoes (Russets or Yukon Gold)
Place the chicken on an even layer on top of the potatoes.
9 ounces shredded chicken
Place the cooked mushrooms and spinach on top of the chicken.
Pour over the sauce so that everything is well covered.
Top with the parmesan and mozzarella. Cover the dish with foil.
¼ cup shredded parmesan, 1 ball fresh mozzarella
Bake in the oven for 90 minutes. Once cooked, place under the broiler until the cheese is browned.
Let stand for 10 minutes before serving.