In a large skillet over medium-high heat, add oil, bacon, and onion and cook 6 to 8 minutes, or until bacon is crisp and onion starts to brown.
Add the cabbage, apple, salt, and pepper and continue cooking 8 to 10 minutes, or until cabbage is wilted. Stir in cream and mustard and cook 2 to 3 minutes, or until heated through.