01 - Set the oven to 350°F (180°C) to warm up.
02 - Slice off the tops of each bell pepper and carefully remove seeds and membranes. Set aside.
03 - Heat olive oil in a large skillet over medium heat. Add chopped onion and cook for 3 minutes until softened.
04 - Add minced garlic and cook for 1 minute. Incorporate ground beef, breaking it up with a spoon, and cook until browned.
05 - Add diced zucchini and tomato to the skillet, cooking for 3 minutes until slightly softened.
06 - Mix in rinsed rice, tomato paste, parsley, mint, oregano, cumin, cinnamon, salt, and black pepper. Cook for 2 to 3 minutes, stirring thoroughly.
07 - Take the skillet off the heat to cool slightly before stuffing the peppers.
08 - Firmly fill each bell pepper with the beef mixture, pressing gently to pack evenly. Place peppers upright in a baking dish.
09 - Pour chicken or vegetable broth at the bottom of the baking dish around the peppers.
10 - Sprinkle crumbled feta cheese and pine nuts over the stuffed peppers.
11 - Cover the baking dish loosely with aluminum foil and bake for 35 minutes.
12 - Remove the foil and continue baking for 10 minutes until peppers are tender and feta is lightly golden.
13 - Let the stuffed peppers rest for 5 minutes before serving to enhance flavor and texture.