Preheat oven to 350 degrees and grease a 9 x 13 casserole dish with 1 tablespoon of ghee.
Peel parsnips and thinly slice on a mandoline.
In a medium-size saute pan, heat 1 tablespoon of ghee. Add in sliced onions and cook on low heat for 15 minutes. Cook until the onions start to brown. Set aside.
Place almond milk and cashews into a high-speed blender. Blend for 1 minute or until smooth. Set aside.
In the greased casserole dish, spread 1 layer of sliced parsnips with ⅓ of sauce, cranberries, thyme, garlic, ½ teaspoon salt, cracked pepper. Repeat 2 more times.
Cover with aluminum foil and bake for 45 minutes. Uncover the parsnips and cook for another 30 minutes, or until golden brown.