Preheat the oven to 375.
Cut the ends off of the zucchini and cut them in half.
Scoop out the inside of the zucchini and discard.
Place the zucchini in a baking dish and sprinkle it with a pinch of salt.
Bake for 15 minutes and prepare the beef.
In a skillet, saute the onion with olive oil for 5-7 minutes.
Add in the beef, salt, pepper, and cinnamon.
Cook until the beef is fully done.
Remove the zucchini from the oven and stuff them with the beef mixture.
Place back into the oven for another 5 minutes.
Drizzle with greek yogurt and another pinch of salt. Enjoy!