Mix together the flour, cumin, salt, and pepper on a large plate. Lightly coat each piece of pork with the flour mixture; set aside. Heat the vegetable oil and butter in a large skillet over medium-high heat. Sprinkle the apple halves with a pinch of salt and pepper. Cook the apples cut-side down about 5 minutes or until golden brown. Remove from the skillet, cover, and set aside. Place the pork in the skillet, sprinkle with the parsley, and cook until the meat is golden brown and crispy, 4 to 5 minutes per side. While the pork is cooking, whisk together the broth and vinegar. Remove the pork from the skillet and set aside. Pour the broth mixture into the skillet, stirring and scraping up any browned bits. Bring to a boil and cook until slightly thickened. Divide the pork among 4 plates and pour some pan sauce over each. Before serving, place an apple half and a dab of mustard on each plate.