2 tablespoons freshly grated lemon zest (from about 2 medium lemons)
1 tablespoon freshly ground black pepper
1 tablespoon kosher salt
FOR THE BRAISE:
4 pounds bison short ribs
1/4 cup olive oil
1 medium yellow onion, large dice
1 medium fennel head, large dice
1 medium celery stalk, large dice
3 fresh thyme sprigs
1 medium bay leaf
2 cups low-sodium beef broth
Heat the oven to 300°F and arrange a rack in the middle.
For the rub:
Place all ingredients in a medium bowl and mix until thoroughly combined; set aside.
For the braise:
Pat ribs dry with a paper towel and cover on both sides with thyme rub. Let meat come to room temperature, about 20 minutes.
Once meat is ready, place a large, shallow pot with a tightfitting lid over medium heat and add oil. When it starts to shimmer, add ribs and sear until well browned on both sides, about 4 minutes per side (you may have to do this in batches).
Remove ribs to a baking sheet and set aside. Add onion, fennel, and celery to the pot and season with salt and freshly ground black pepper. Stir, scraping up any browned bits stuck to the bottom of the pan. Cook until vegetables are tender and browned, about 10 minutes. Stir in thyme, bay leaf, and broth, then place ribs bone side up in the pot and bring mixture to a boil.
Once boiling, cover the pot and transfer it to the oven. Cook ribs until meat falls apart when pierced with a fork, about 4 hours