Heat the olive oil in a large Dutch oven over medium-high heat. Add the pork cubes and brown them on all sides, about 6 to 8 minutes. Remove the pork and set it aside.
Lower the heat to medium. Add the onion and cook until it softens, about 4 minutes. Stir in the garlic and cook for 1 minute more.
Add the shredded cabbage and stir for 3 minutes until it begins to wilt.
Pour in the dark beer and scrape the bottom of the pot to release any browned bits. Stir in the Dijon mustard, beef broth, and thyme.
Return the pork to the pot. Season with salt and black pepper. Bring the mixture to a simmer, then cover and cook for 45 minutes until the pork is tender.
Taste and adjust seasoning if needed. Sprinkle with chopped parsley before serving.