While your potatoes are cooking, pour one tablespoon of oil into a skillet and sauté the onion and garlic over medium-high heat. Incorporate the ground beef and stir well to break up any large pieces stuck together. Next, add the cumin, salt and pepper while stirring continuously. If you wish, sprinkle the ají panca over the meat, then mix-in the raisins and chopped cilantro. Keep stirring until most of the juice has evaporated or been absorbed. When ready, remove from heat.