Preheat oven to 450 degrees F (230 degrees C).

Scoop pulp out of each zucchini half with a spoon and discard. Arrange zucchini in a deep glass baking dish.

Stir 1 teaspoon cinnamon, 1/2 teaspoon minced garlic, and 1/2 teaspoon pepper into each can of chicken broth.

Combine turkey, rice, and garlic powder in a large bowl; mix thoroughly. Stir in 1 can seasoned chicken broth.

Stuff each zucchini half with turkey mixture. Place top halves over bottom halves so they look like whole zucchini. Pour the second can of seasoned chicken broth over zucchini and into the baking dish. Cover with aluminum foil.

Bake in the preheated oven until rice is tender and zucchini is soft, about 1 hour 15 minutes.