Grate sweet potatoes in food processor.
Set aside on paper towels to drain.
Spray muffin tins with cooking spray.
(Olive oil, avocado or coconut oil all work well).
Fry bacon in large skillet until crisp but not scorched.
Drain on paper towels.
Crumble bacon and set aside.
Pat the sweet potatoes between layers of paper towels to remove any excess liquid.
Transfer the sweet potatoes to a large mixing bowl.
Add green onions, Parmesan cheese, Cheddar cheese, the crumbled, cooked bacon, salt, pepper, thyme, parsley and olive oil.
Stir ingredients well to combine.
Press sweet potato mixture firmly into prepared muffin tins.
Bake in a preheated 400º oven for about 45 minutes, or until sweet potato nests are crispy.