1) Place the lentils in a large saucepan. Cover with water and rub them with your fingers. Drain the water and repeat this process 3 - 4 times until the water is no longer cloudy; drain again well. Add 4 cups of water to the lentils and bring to a boil over medium-high heat. Skim off the foam that rises to the top. Add the potatoes and return to a boil. Reduce to medium heat and simmer for 5 minutes, uncovered.
2) Stir in the green beans, squash or eggplant, cauliflower, carrots, salt and turmeric. Return to a boil, cover and reduce to a gentle simmer. Cook, stirring occasionally, about 10 minutes.
3) Meanwhile, heat oil in a small skillet over medium-high heat. Add the cumin seeds and cook until they sizzle and smell fragrant, about 20 seconds. Stir in garlic and chiles (to taste) and cook, stirring, until the garlic begins to brown, about 1 - 2 minutes. Remove the seasoning mixture from the heat and add to the cooked vegetables. Use some of the cooking liquid to deglaze the skillet and pour back into vegetable pot.
4) If the curry is as thick you like, go ahead and add the ginger, optional cilantro, and lime juice. If you want to thicken the curry a little more, either cook it for a few minutes longer, uncovered, or place some of the curry into a separate bowl and puree it with a hand-held blender. Then add the pureed mixture back into the pot. Beware, it will thicken with time so you may want to wait to see if you like the consistency prior to serving it. Enjoy!