Season both sides of the meat with salt, pepper, onion powder and garlic powder to coat. Massage with hands to adhere to the meat, and make sure all is coated.
Add oil to a large cast iron pot/Dutch oven and raise to medium/high heat. Add the meat and sear on both sides until golden. Remove from the pot and place on a plate. Add the onions and sauté for 5-8 minutes until softened. Add in the jar of Mikee’s and mix together. Add the meat back in, top with rosemary, and bring to a boil. Lower to a simmer and cover with a tight-fitting lid.
Place in the oven and cook for about an hour. Pull oven rack out, flip meat over and cover again. Continue cooking for another 2 hours or so until the meat is super soft. Let cool, remove the rosemary sprigs, and slice and serve fresh with the sauce!