Prep & Sear: Pat the roast dry with paper towels. Season generously with salt and pepper. Heat your oil in a cast-iron skillet over medium-high heat. Sear the roast on all sides until a deep, golden-brown crust forms. This crust is where the flavor lives—do not skip this!
Deglaze: Remove the roast. Add onions to the hot skillet, cooking for 2 minutes. Stir in the tomato paste and garlic for 1 minute. Pour in the red wine and Worcestershire, using a wooden spoon to scrape up all those delicious brown bits from the bottom of the pan.
Assemble: Place the seared roast in the slow cooker. Nestlé the potatoes and carrots around the sides (not directly on top of the meat if you want them firmer). Pour the liquid mixture over everything. Top with the fresh herbs.
Low & Slow: Cover and cook on LOW for 8–9 hours. Avoid the temptation to turn it to "High"—lean game meat needs the gentle, sustained heat of "Low" to break down connective tissue without seizing up.
Finish: Once the meat falls apart easily with a fork, remove the roast and shred it. If you want a thicker gravy, whisk a tablespoon of cornstarch with a splash of cold water and stir it into the juices in the slow cooker for the final 15 minutes.