Line a large baking sheet with foil (for easy clean up).
Put the sweet potatoes in a bowl and toss with about 1/3 cup olive oil and 1/2 tsp cinnamon, 1/2 tsp salt and 1 tsp black pepper then place on one end of the baking sheet (see picture).
Toss cauliflower pieces with about 2-3 tablespoons of olive oil and salt and pepper, place on the other end of the baking sheet (see pic).
Pat the chicken with paper towels and then rub remaining olive oil on both sides and season both sides with Italian seasoning, place in the center of the baking sheet (see pic).