1. Generously season the roast with salt and pepper on all sides. Add a bit of oil to a pan on medium-to-high heat, and brown each side of the roast until it has a nice golden brown crust. Transfer to a slow cooker.
2. Mix together the BBQ beef mixture and pour over the roast. Turn the slow cooker on low for 7-8 hours. When finished, shred the beef and add it back to the liquid mixture.
3. Boil the potatoes and mash them with 1-2 Tbsp of butter until soft. Add salt & pepper as desired.
4. In an oven or air fryer, roast the veggies until golden brown. The carrots will take longer than the broccoli & zucchini.
5. Plate with mashed potatoes on the bottom, the beef & veggies on top. Add a generous dollop of horseradish (optional) and garnish with green onion. Enjoy!