Anticipation is a great thing, and with a meal that has such lush rewards, it’s worth taking your time. This isn’t a Thursday night thing, but a lazy Sunday that builds up to a real payoff in flavors and satisfaction.
Preheat your oven to 350 degrees. Season all the short ribs with salt and pepper, and set aside. Heat a Dutch oven, or any wide, shallow pot with a lid, on the stove over medium-high heat. Stir in the olive oil and butter until the butter melts. Stir in the onion, and cook until it begins to soften, about 3 minutes. Remove and set aside.
Brown the short ribs in the hot Dutch oven until browned on all sides, about 3 minutes per side. Once browned, add the onions back into the pot; then pour in the wine, beef stock, tomatoes, and Portland Bloody Mary Mix. Bring to a simmer, then cover, and place into the preheated oven for 3 hours. In the last 30 minutes, you might also want to throw some carrots, fingerling potatoes, and/or mushrooms in there while you’re at it.