Begin by shredding the zucchini using a grater, then place it in a clean kitchen towel to squeeze out excess moisture.

In a large mixing bowl, combine the shredded zucchini, ground chicken, panko breadcrumbs, egg, basil pesto, lemon zest, and seasonings. Mix well and form into 16 meatballs.

In an oven-safe skillet, heat olive oil over medium-high heat. Add meatballs and brown for about 6 minutes, turning occasionally.

In the same skillet, add baby bella mushrooms with a pinch of salt and pepper. Sauté for 5-8 minutes until golden brown, then add minced garlic for an additional minute.

Add chicken broth, milk, basil pesto, lemon zest, and uncooked orzo to the skillet. Stir gently and return meatballs, bringing to a simmer.

Preheat your oven to 400°F (200°C). Transfer the skillet to the oven and bake for 10-12 minutes.

Remove the skillet from the oven, sprinkle mozzarella cheese on top, and return for another 5 minutes or until melted.