Remove the boneless short ribs from the fridge and let them sit at room temperature for 30 minutes.
Pat the short ribs dry and season with salt, pepper, and garlic powder.
Heat olive oil in a cast iron skillet over medium-high heat.
Sear the short ribs for 3 minutes per side until browned.
Remove the ribs and sauté diced onion and garlic in the same pan.
Deglaze the pan with red wine, scraping up any browned bits.
Pour in the beef broth and add rosemary.
Return the ribs to the pan, cover, and reduce the heat to low.
Simmer the boneless short ribs gently for 2.5 to 3 hours until fork-tender.
Serve with your favorite sides and drizzle with pan sauce.