To stuff and roll the cabbage leaves, lay a cabbage leaf flat on a cutting board, scoop out 2 tablespoons of the rice mixture into the center of the cabbage leaf, and carefully roll it slowly and tightly, but without tucking in the corners. Squeeze the cabbage roll to help secure it and set aside. Repeat until all the stuffing has been used and place the stuffed cabbages on a tray. It should yield 30-35 rolls.
Line the bottom of a large pot with the small cabbage stems and tomato slices and season with cumin. Neatly arrange the stuffed cabbage in rows, alternating directions, to completely cover the circumference of the pot. Add the sliced garlic along with tomato slices, green peppers if using, and cumin.
Place a small round plate on top of cabbage in the pot to hold them down and prevent floating while they are cooking. You can also place a heavy pot filled with water to hold them in place
Add 6 cups of water to completely cover the cabbages leaves and the plate, then cover the pot and cook on medium heat for 30 minutes. You want most of the water to be absorbed (there should still be some at the bottom of the pot) and the leaves to be tender
Add the lemon juice on top of the cabbage leaves, then cook on low heat for an additional 45 minutes.
Remove from heat and let cool uncovered for 30 minutes. Transfer to a dish and enjoy warm!