Line a large baking sheet with parchment paper or a silicone baking mat. Cut the sweet potato (1 large) into half inch pieces. Half the brussels sprouts (1 lb). Place the sweet potato cubes, Brussels sprouts, and minced garlic (2 cloves) on the baking sheet. Drizzle oil over vegetables then gently toss to coat and sprinkle with salt and pepper before spreading them out so that they’re in a single layer.
Place the baking sheet in the oven and roast the vegetables for 15 minutes.
While the vegetables are roasting, mix the ground beef (1 lb) with BBQ sauce (1/4 cup), garlic powder (1/2 tsp) and onion powder (1/2 tsp), thyme (1/4 tsp), salt, and pepper. Divide the meat mixture into 4 portions and shape each into a football shape about ¾-inch thick. Set aside.
After the vegetables have been in the oven for 15 minutes, remove the baking sheet from the oven. Stir vegetables then make a space between them for the meatloaves.
Place the meatloaves on the pan and spread the remaining BBQ sauce (some) over each one.
Return the baking sheet to the oven and bake for an additional 12-15 minutes or until an instant-read thermometer inserted into the thickest part of the meatloaves registers 165 F.
Remove the baking sheet from the oven, sprinkle with chopped parsley (if desired) and serve immediately.