Peel and coarsely dice onions. Heat oil in large pan, add onions and cook over low heat for 15 minutes. Peel and mince garlic and ginger. Stem, seed and mince chiles. Coarsely chop tomatoes, reserve juice. Stir ginger, garlic, chiles, half of the tomatoes, all the reserved tomato juice, lemon juice and paprika into pan. Cook for 2 minutes, then add coconut milk. Put macadamia nuts in food processor, process until finely ground, add to soup. Put cilantro leaves in processor and chop, add 1/2 leaves to soup. Transfer soup to processor and puree adding stock with machine still running. Return to pan, add remaining tomatoes and chopped cilantro. Bring soup to a boil. Season with salt and black pepper. Cover and keep warm. (Can be cooled, covered and refrigerated up to 2 days.) If soup has been refrigerated, bring to simmer just before serving. While soup is still very hot add Shrimp, Scallops, and fish. Keep lid on for 5 minutes to allow hot liquid to cook fish trough. Be careful not to overcook. Serve immediately and garnish with cilantro leaves.