Cut the cabbage head in half and blanch: Place cabbage in a large pot of boiling water for 3-5 minutes until leaves soften and can be peeled without tearing. Remove from heat and let cool slightly.
Blanch cabbage leaves: Remove leaves one at a time, blanching them briefly if needed, while saving the core to use as a base for stacking the rolls in the pot.
Prepare rice filling: In a large skillet, heat olive oil over medium heat. Add onion and garlic, sauté until soft and fragrant. Stir in rice, oregano, cumin, salt, and pepper. Cook for 2-3 minutes, then stir in chopped parsley, dill, lemon zest, and vegetable broth. Cook for another 5 minutes to create a fragrant, slightly moist filling. Remove from heat and let cool slightly.
Stuff the cabbage leaves: Working with one leaf at a time, spoon about 2 tablespoons of rice mixture near the base of each leaf. Roll tightly, tucking in the sides, and place seam-side down in a large, deep oven-safe skillet with the cabbage core at the bottom. Repeat with remaining leaves and filling.
Prepare the sauce: In a separate bowl, combine chopped tomatoes, olive oil, balsamic vinegar, chili flakes (if using), and a pinch of salt. Stir well. Spoon the sauce evenly over the cabbage rolls and core in the skillet.
Simmer the rolls: Cover the skillet with a lid or aluminum foil and simmer over low heat for 30-35 minutes, ensuring the sauce keeps the rolls tender and moist. Occasionally check that the liquid hasn’t evaporated, adding a bit more broth or water as needed.
Serve: Remove from heat, let sit for 5 minutes, then garnish with chopped parsley and dill. Serve warm with a side salad and crusty bread.