Preheat the oven to 400 degrees. Add the basil, water, Parmesan, almonds, olive oil, garlic, lemon juice, salt, and pepper to a food processor. Pulse until combined to make homemade pesto. You can also swap in store-bought pesto.
Spray a baking dish with cooking spray. Place the chicken in the dish and season with salt and pepper. Spread the pesto on top of the chicken. Then top with sliced tomatoes and ¼ cup cheese per chicken breast.