Preheat oven to 450 degrees F. Spray a rimmed baking sheet (I use this one) with cooking spray.
Prepare the Vegetables:
Place the broccoli florets on one side of the baking sheet and the potatoes on the other side. Drizzle with 2 tablespoons olive oil and sprinkle with salt and pepper. Toss to coat.
Prepare the Chicken:
Place the chicken breasts down the center of the baking sheet.
In a small bowl or liquid measuring cup, whisk together the lemon juice, olive oil, honey, rosemary, salt and pepper. Pour over chicken.
Lay a few lemon slices on the pan for garnish, if desired.
Bake for about 20 minutes, until chicken is cooked through. Chicken should register at least 165 degrees F on an instant-read thermometer. Exact chicken cook time will depend on the size and thickness of your chicken breasts.