Preheat Oven: Set your oven to 180°C (350°F) and grease a baking dish.
Sauté Aromatics: Heat olive oil in a pan over medium heat. Add chopped onion and cook until softened, about 3 minutes. Stir in garlic, smoked paprika, smoked garlic powder, and Italian herbs. Cook for another minute until fragrant.
Prepare the Filling: Add lentils, rice, walnuts, canned tomatoes, date syrup, and vegetable stock. Stir well and let it simmer for 10-15 minutes, until slightly thickened.
Assemble the Dish: Spread half of the chopped cabbage in the baking dish. Pour the lentil-walnut mixture over it, then top with the remaining cabbage.
Bake: Cover with foil and bake for 40 minutes. Remove foil and bake for another 10 minutes for a slightly crispy top.
Garnish & Serve: Let it rest for 5 minutes before serving. Garnish with chopped chives and serve with plant-based yogurt if desired.