Preheat oven to 375 deg. F
Caramelized Onions and Mushrooms: Heat 1 tsp oil and 1 tsp ghee in a pan on medium heat. Once ghee is melted add sliced onions and sautee until starting to soften. Add minced garlic and mushrooms to the pan. Stir intermittently until onions and mushrooms have carmalized (around 10 minutes).
Hash brown Crust: While onions and mushrooms are cooking, add 1 teaspoon of ghee and 1 teaspoon of olive oil to a 10" cast iron skillet on medium heat. Add about 4 cups of frozen or fresh shredded hash browns (enough to cover the botton of the pan) and press down to evenly distribute. Continue to intermittently press down as the potatoes soften. Allow to cook until bottom is brown and crispy (about 10 minutes), then turn off heat.
Cauliflower Rice: While hash browns and mushrooms and onions are cooking, add 1.5 cups of frozen cauliflower rice to a microwave safe bowl and microwave for 4 minutes.
Whisk eggs, egg whites, thyme, rosemary, and a dash of salt and pepper to a bowl and whisk.
Add caramelized onions, mushrooms, cauliflower rice, and chicken sausage in with the eggs and mix well.
Pour egg mixture into the cast iron skillet with the hash brown crust. Transfer to oven and bake for approximately 35-40 minutes or until the center is set and top is golden brown.
Let cool for a few minutes and then use a sharp or serrated knife to cut and serve. This tastes great warm and cool!