Preheat your oven to 350°F (175°C).

Fill a large pot with water and add a generous amount of salt. Bring it to a boil, then gently add the zucchinis and allow them to boil for 5 minutes.

Once the zucchinis are cool, slice each in half lengthwise and scoop out the seeds and flesh.

Grease a 9x13 inch baking dish with olive oil.

In a skillet, heat olive oil over medium heat, then sauté the chopped onion for 3-4 minutes.

Add the ground turkey and cook until no longer pink, about 5-7 minutes.

Mix in garlic, diced tomatoes, tomato paste, reserved zucchini flesh, water, salt, pepper, and red pepper flakes. Simmer for 10-12 minutes.

Remove from heat and mix in Parmesan cheese and half of chopped parsley.

Spoon the filling into each zucchini half and sprinkle Monterey Jack cheese on top.

Place in the prepared baking dish and bake for 25-30 minutes.