How to Make It
Heat oven to 325° F. Heat 2 tablespoons of the oil in a large pot over medium-high heat. Season the pork with the cumin, 1½ teaspoons salt, and ½ teaspoon pepper. In batches, brown the pork, turning, 6 to 8 minutes; transfer to a plate as it browns.
Add the flour and the remaining 2 tablespoons of oil to the pot and cook, stirring, for 1 minute. Add the orange juice, tomatoes, garlic, jalapeños, and 4 cups water and bring to a boil. Return the pork to the pot. Cover the pot, transfer to oven, and cook until the pork is tender, 2½ to 3 hours.
Meanwhile, in a bowl, toss the onion, vinegar, ½ cup water, and ½ teaspoon salt. Let sit, tossing occasionally, for at least 30 minutes and up to 3½ hours.
Skim and discard any fat from the stew. Add the okra. Cover the pot, return it to oven, and cook until the okra is tender, about 15 minutes. If the stew is too thin, place the pot on the stove and simmer, uncovered, until thickened, 5 to 10 minutes more.
Fifteen minutes before the stew is done, cook the grits according to the package directions. Serve with the stew and onions.