Heat the oil in a heavy bottom skillet or Dutch oven, over medium-high heat. While the oil is heating, generously season the chuck roast with kosher salt pepper on each side. Add the seasoned roast to the heated oil and sear on each side until browned, about 2-3 minutes per side, or once the meat easily pulls away from the pan.
Pour beef stock into slow cooker, add potatoes, carrots, garlic and onion powder if using. Lay the roast on top of the potatoes and vegetables. Spread the roast with a thin layer of the horseradish to coat.
Cover and slow cook on low heat for 10-12 hours or on high heat for 5-6 hours.
After slow cooking, place the roast into a shallow serving dish or large bowl and let rest briefly. Remove the potatoes and carrots from the slow cooker using a slotted spoon, placing them onto a platter or serving dish. Shred the roast with two forks and serve with the potatoes, carrots, and reserved cooking liquid as desired.
Pot Roast Gravy (optional)
Strain 2 cups of the cooking liquid into a small saucepan and bring to a simmer over high heat. Whisk together 2 tablespoons of cornstarch with ¼ cup cold water in small bowl. Whisk cornstarch slurry into the simmering liquid, and cook, stirring constantly, until thickened, about 5 minutes. It will only take a couple minutes. Alternatively, you can whisk cornstarch into slow cooker and cook on high, stirring often for 30 minutes.
Video
Notes
Horseradish: Use prepared horseradish which is is just pre-grated fresh horseradish you find in the refrigerated section of your grocery store. The only ingredients should be horseradish, salt, and vinegar. Potatoes: In place of baby potatoes, use larger Yukon gold or russet potatoes cut into large 2-inch chunks. Carrots: Feel free to use regular carrots, peeled and cut into 2-inch chunks.Roast: The best cut of beef to use for a pot roast is a chuck roast, as it is marbled and will be exceptionally tender. Storage: Store leftovers in an airtight container in the refrigerator up to 3 days. Use the cooking liquid for gravy, soups, or stews as desired. Freeze Leftover Beef: Place beef and cooking liquid into a freezer-safe container, leaving space for expansion. Store in the freezer for up to 3 months. Defrost overnight in the fridge before reheating and serving.