Mushroom Beef Stew

1 lb. beef round roast, cut into 1-inch cubes
3/4 t. sea salt
1/2 t. freshly ground black pepper
2 T. arrowroot
2 T. macadamia nut oil
1 large onion, coarsely chopped (about 1-1/2 C.)
8 oz. white mushrooms, sliced
4 oz. shiitake mushrooms, stemmed and sliced
1 T. fresh thyme leaves
4 cloves garlic, minced
3 stalks celery, cut into 1-inch pieces
2/3 C. dry red wine (or sub additional beef broth
3 T. tomato paste
2 C. low-sodium beef broth
1 small sweet potato (about 6 oz) peeled and cut into 3/4-in cubes

Season the beef with 1/4 t. of salt and 1/4 t. pepper in a medium bowl.  Add the arrowroot and toss to coat. 

Heat 1 T. oil in a Dutch oven over medium-high heat.  Add the beef and cook, turning occasionally, until browned 4-5 minutes.  Transfer to a plate.

Return the Dutch oven to the stove and heat the remaining 1 T. oil over medium heat.  Add the onion, mushrooms, and thyme and cook, stirring occasionally, until slightly browned, 8-9 minutes.  Stir in the garlic and celery and cook for 2 minutes.  Stir in the wine and tomato paste and bring to a boil; cook for 1 minute.  Add the broth and the reserved beef, and return to a boil.  Immediately reduce the heat to medium-low, cover the pan, and simmer gently until the beef is nearly tender, about 40 minutes.  Stir in the sweet potato and remaining 1/2 t. salt and 1/4 t. pepper, and return to a gentle simmer.  Cook until the beef and potato are tender, about 20 minutes.