In a large stainless steel or cast iron skillet, over medium heat, cook ground pork, shiitake mushrooms, carrots, onion and garlic. Add 1 tablespoon of butter, ghee or coconut oil if your pork very lean.
While your pork and vegetables are cooking, remove the outer 8-10 large leaves from your napa cabbage, set aside. finely chop or shred 4 small napa cabbage leaves (you are saving the largest leaves for your rolls)
Add your shredded cabbage and remaining ingredients to your skillet and season to taste with sea salt and pepper. Continue to cook until vegetables are soft and pork is cooked through. When done, remove from heat and set aside.
In a large pot fitted with a steamer insert, bring 1 cup of water to a boil. Steam napa cabbage leaves for 1 minute, working in batches of 3-4 leaves at a time. Place steamed leaves in a colander to drain.
Return filling to the stove and heat over medium/low.
Lay out a steamed napa leaf, with the stem towards you and the leafy portion pointing away. Trim off any excess stem. Place roughly 1/8 of the warm filling mix on the stem end of the napa cabbage leaf, about an inch from the edge. Fold the bottom stem up and over the filling, rolling to catch the edge. Then fold in the sides and continue rolling, using a toothpick to secure.
Serve immediately with Thai Sweet Chili Sauce.