Cook onions in ½ tablespoon ghee till softened. Add cumin seeds with ¼ tablespoon ghee and cook for a few minutes, till the seeds are toasted. Add minced garlic and cook for a few minutes. Add the rest of the spices and cook a few minutes, till fragrant.
Toss in the sliced watermelon rind. Add the remaining ghee and sauté for a few minutes to mix well. The watermelon rind should not be coated in all the spices and ghee.
Add a few tablespoons of water or more as needed, mix and cover for about 10–15 minutes on medium low, stirring occasionally. Continue to cook till the watermelon rind has softened and absorbed all the spices. Top with fresh cilantro and serve as a side dish.