Preheat your oven to 275 F.
Season the chuck to taste with sea salt and black pepper.
Sea salt and freshly ground black pepper to taste, 3 ½ lbs. beef chuck
On the stovetop, warm the coconut oil in a Dutch oven over high heat, and brown the beef on all sides.
Remove the chuck. Add all the remaining ingredients to the Dutch oven and reduce the heat to medium-low.
1 cup carrots, 1 cup celery, 1 large onion, 2 tsp. fresh rosemary, 1 tbsp. cooking fat, Additional ¼ cup Paleo cooking fat or ghee
Cook the vegetables for about 5 minutes, stirring frequently.
Return the beef to the pot. Cover and roast in the oven for 2 hours or until the beef is fork tender.
Let the beef rest and serve with the braised vegetables.