Preheat oven to 350 degrees F. Prepare jars by lightly spraying with avocado oil and placing on a cookie sheet. Set aside.
In a skillet over medium heat, cook sausage until no longer pink. Remove from skillet, drain and set aside.
In the same (dirty) skillet, cook kale, onion and garlic in ghee over medium heat until soft and cooked through. Season with a pinch of sea salt & black pepper, crushed red pepper and lemon juice. Remove from heat.
Add sausage to kale mixture and mix well. Divide between prepared jars and top with shredded cheese.
Season beaten eggs with sea salt and pepper. Divide between jars and using a fork lightly mix.
Bake for 20 minutes at 350 degrees or until cooked through*.
Allow to cool completely, then cover with a lid and refrigerate. Reheat for a quick, make-ahead breakfast.
*They will puff up when cooked through, but will fall back to fit into the jar while cooling.