Preheat oven to 400 degrees F. Cut squash in half, scoop out the seeds and place cut side down on a baking sheet lined with parchment paper. Bake for 30 minutes, remove from the oven and set aside to cool.
Meanwhile, preheat large skillet on high heat and spray with cooking spray. Add mushrooms and saute for 5 minutes or until golden brown, stirring occasionally. Transfer to a medium bowl.
Return skillet to medium-high heat and spray with cooking spray. Add onion and garlic and cook for 2 minutes, stirring frequently. Add kale, 1/2 teaspoon thyme, 1/4 teaspoon salt and 1/4 teaspoon pepper and saute until kale is wilted. Transfer to a bowl with mushrooms and set aside.
To make the crust, separate spaghetti squash into strands with a fork. Add to a medium bowl along with thyme, onion powder and salt, and mix to combine. Transfer to a deep pie dish and press evenly on the bottom and sides using your hands. Set aside.
In a large bowl, combine eggs with egg whites and whisk for 30 seconds. Add cheese, cottage cheese, previously cooked mushrooms and kale, 2 teaspoons onion powder, 1 teaspoon thyme, 1/4 teaspoon salt, 1/2 teaspoon pepper and mix to combine.
Pour into prepared crust and flatten with spatula to make sure all vegetables are covered with liquid. Bake in 400 degrees F oven for 50 mins or until the knife inserted comes out clean.
Let quiche cool down for at least 30 minutes. Cut into 8 slices and serve hot or cold.
Notes
Store: Refrigerate covered for up to 3 - 4 days. Do not freeze.