Heat 1 teaspoon of oil in a saucepan over medium heat. Stir in the chopped onion, and cook until the onion turns translucent and the edges begin to brown, about 7 minutes. Scrape the onion into the container of a blender, and set aside. Return the saucepan to the stove, and stir in the curry leaves and peppercorns. Cook and stir until the curry leaves wilt and turn almost dry, about 5 minutes. Stir in the coriander, and cook 1 minute more. Scrape the curry leaves into the blender, and pour in 1/2 cup of water. Blend until the mixture has turned into a coarse paste.
Heat 3 tablespoons of oil in the saucepan over medium heat. Stir in the sliced onions, and cook until the onions have softened and turned translucent, about 5 minutes. Stir in the ginger and garlic, continue cooking until the garlic softens and mellows, about 3 minutes more. Stir in the cayenne pepper, salt, and turmeric; continue cooking 2 minutes. Finally, stir in the tomato paste, goat meat, pureed peppercorn sauce, and the remaining 1/2 cup of water. Bring to a simmer, then reduce heat to medium-low, cover, and simmer until the meat is tender, about 30 minutes.
