Preheat the oven to 375°F. Spray an oven safe baking dish with non-stick cooking spray and set aside.
Make the pesto according to the directions in my blog post or use a store bought jar.
Using a sharp knife, cut a horizontal slit along the thin, long edge of the chicken breast, nearly through the opposite side. Open up each chicken breast and place 2-3 Tbsp. of the pesto in the center. Sprinkle with 2-3 Tbsp. mozzarella.
Pinch chicken breasts closed and use toothpicks to secure. Repeat with remaining chicken breasts. Scatter the cherry tomatoes in the pan around the chicken. Pour lemon juice over the chicken, followed by the olive oil and season with salt and pepper. Cover pan with foil.
Bake in the oven for 45-55 minutes or until the chicken is cooked to an internal temperature of 165°F. Enjoy with side dishes of your choice (we like pasta and a veggie such as broccoli, Brussels or salad).
Will last in fridge for up to 4 days. Makes great leftovers for lunch!Serve with pasta, zoodles, asparagus, Brussels, broccoli, salad.