Place the cumin seeds into a dry skillet over medium heat, and toast them, stirring constantly, until they give off a roasted fragrance and turn a darker brown, about 1 minute. Scrape the seeds into a bowl, and allow to cool. When cool, grind them with a mortar and pestle or a clean spice grinder. Set the ground seed aside.
Remove stems of chiles if necessary, and soak pods in the apple cider vinegar in a bowl until soft, at least 1 hour. Place the softened chiles with vinegar, cumin, and garlic into a blender or food processor, and pulse until ground into a paste, 30 seconds to 1 minute or as needed.
Heat the vegetable oil in a large pot over medium heat, and cook and stir the onions until lightly browned, about 10 minutes. Stir in ginger garlic paste and about 1 teaspoon of the Grandmother's Chile Paste mixture or as desired. Reduce heat to medium-low, and fry the onions with the spice pastes for 5 minutes to blend flavors. Stir in tomato paste, ground red pepper, turmeric, cinnamon, and cloves, and bring to a simmer. Cook to blend flavors, about 20 minutes.
Mix in the lamb shank pieces, and stir in salt to taste; simmer for 20 minutes, and stir in the water. Bring the lamb and sauce to a boil, reduce heat to a simmer, and simmer until lamb is very tender and sauce has thickened, 45 more minutes. Sprinkle with chopped cilantro to serve.