Preheat oven to 450°F. Prepare one large baking dish and lightly coat with 1 tbsp olive oil. Season the chicken breasts with salt, pepper, and Italian seasoning.
In a large bowl, toss the sliced zucchini, squash and onion with 1 tbsp olive oil until evenly coated. Season with salt, pepper, and Italian seasoning.
Cover each chicken breast with 1/4 cup of hummus each. Then place on top of the vegetables. Place all vegetables on the bottom of a 9×13 dish in an even layer. Lay the chicken evenly on top. Squeeze the juice of one lemon over the chicken and vegetables.
Lightly season the entire dish with chopped rosemary and paprika. Thinly slice the remaining lemon, and place a few thin slices in the dish.
Drizzle balsamic vinegar over the top, then bake for about 25-30 minutes, until the chicken is cooked through and the vegetables are tender. Serve immediately.