I saw something like this on my friend Lauren's blog a couple years ago and wanted to try to make it myself. We had a giant zucchini in our garden so I thought I'd give it a shot. The pictures below show the process. For the ground turkey I threw in some onion powder, garlic powder, Italian seasoning, and some salt and pepper. I just used a can of diced tomatoes but I'm sure tomato sauce would work too (and Rach would like it more). I baked them at 375 for 30 minutes.
Large fresh zucchini
Used our Pampered Chef melon baller to scrape the insides out
Cheese first (I only had cheddar)
Diced tomatoes from a can
More cheese (obviously)
Italian Bread Crumbs and Basil