Preheat the oven to 400°F (200°C). Toss the sweet potatoes and brussels sprouts with 1 tablespoon of sesame oil, salt, and pepper. Spread on a baking sheet and roast for 25-30 minutes.
In a mixing bowl, combine ground beef, panko breadcrumbs, milk, scallions, ginger, garlic, salt, and Gochujang. Form into meatballs and place on a baking sheet.
In a saucepan, mix soy sauce, maple syrup, rice vinegar, garlic, ginger, and Gochujang. Simmer for 5 minutes. Mix cornstarch and water, then add to the sauce to thicken.
Bake the meatballs in the oven for 15-20 minutes until fully cooked.
Serve the meatballs over roasted vegetables and drizzle with BBQ sauce. Top with sesame seeds and green onion.