Place chicken tenderloins in a zip bag. Mix lemon juice, 2 tablespoons olive oil, mustard, garlic, rosemary, salt, and pepper. Pour over chicken and marinate for at least 1 hour.
Preheat oven to 400°F and prepare a baking sheet.
Peel and cube sweet potatoes. Toss with oil, cumin, garlic powder, salt, and pepper. Roast for 15 minutes.
Toss asparagus and bell pepper with remaining oil and seasoning.
Heat oil in a skillet over medium heat and cook chicken 4–5 minutes per side until fully cooked.
Add vegetables to the pan with sweet potatoes and roast another 12–15 minutes.
Assemble Chicken and Roasted Vegetable Bowls with rice, chicken, and veggies. Drizzle with dressing if desired.