Steps
1. Heat olive oil in a skillet over medium-high heat.
2. Season the beef with salt and pepper, then sear it in the skillet until browned on all sides.
3. Remove the beef and set aside. In the same skillet, add the onions and garlic, cooking until softened and caramelized.
4. Add the sliced mushrooms and cook until they release their moisture and are golden brown.
5. Return the beef to the skillet and pour in the dark beer. Bring to a simmer.
6. Cover and reduce heat to low, allowing to braise for about 45 minutes, or until the beef is tender.
7. Serve hot, garnished with fresh parsley if desired.