Preheat the oven to 400°F and line a large baking sheet with parchment paper.
In a mixing bowl, combine the ground chicken, panko breadcrumbs, egg, 1/3 cup teriyaki sauce, salt, and black pepper until evenly mixed.
Divide the mixture into four equal portions and shape each into a small loaf. Place the loaves on the prepared baking sheet.
In the same bowl, toss the broccoli florets and sliced bell peppers with the olive oil, salt, and black pepper.
Arrange the vegetables around the meatloaves on the baking sheet in a single layer.
Bake for 20 minutes, then brush the tops of the meatloaves with the remaining 2 tablespoons of teriyaki sauce.
Continue baking for 5 to 8 more minutes until the meatloaves reach an internal temperature of 165°F.
Remove from the oven and sprinkle sesame seeds over the meatloaves before serving.