01 -
Preheat the oven to 350°F (175°C). Lightly grease a baking dish or spray with non-stick cooking spray.
02 -
Melt the butter in a skillet over medium heat. Add the diced red onion and cook until translucent, about 3-4 minutes.
03 -
Stir in the minced garlic and cook for an additional 2 minutes until fragrant.
04 -
Add the chopped chicken pieces to the skillet and cook, stirring occasionally, until browned on all sides and fully cooked through, about 6-8 minutes.
05 -
Pour in the pasta sauce and bring to a simmer. Cook for 5 minutes, then stir in the shredded mozzarella cheese until melted and incorporated. Remove the skillet from heat.
06 -
Using a spoon, carefully scoop out the center flesh of each zucchini half to create hollow 'boats', leaving a sturdy shell.
07 -
Place zucchini boats cut side up in the prepared baking dish. Season each with salt and black pepper. Fill each with the chicken and cheese mixture. Sprinkle grated Parmesan cheese evenly over the tops.
08 -
Bake in the preheated oven for 30 minutes, or until the zucchini is tender and the cheese is golden and bubbly.
09 -
Remove from oven and serve immediately, garnished with chopped fresh parsley.