• Preheat the oven to 375°F (190°C).

Beef Lentil Filling

• In a large skillet, cook the ground beef over medium-high heat until browned. Add the onion and garlic and cook until the onion is translucent.
• Add the cooked lentils, soy sauce, and beef broth to the skillet with the beef mixture. Mix everything together and cook for a few minutes until the liquid is absorbed.

Marinara Sauce

• Meanwhile, in a medium-sized saucepan, sauté the garlic in olive oil over medium heat until fragrant. Add the tomato paste and sugar and cook for 2-3 minutes until darkened.
• Add the crushed tomatoes, bay leaf, basil, parsley, thyme, and soy sauce. Bring the sauce to a simmer and let it cook for 10-15 minutes, stirring occasionally.

Topping

• Mix the melted butter, breadcrumbs, parmesan cheese, parsley, and garlic powder in a bowl.

Assemble Stuffed Peppers

• Cut off the tops of the bell peppers and remove the seeds and membranes. Stuff the peppers with the beef lentil mixture and place them in a baking dish.
• Spoon the marinara sauce over the stuffed peppers, followed by the cheesy breadcrumb topping over each one.
• Cover the baking dish with foil and bake for 30 minutes. Remove the foil and bake for an additional 15 minutes or until the topping is golden brown and the peppers are tender. Serve over rice if desired.