Mix together curry powder, ginger, tamarind paste, garlic, and cinnamon and add enough malt vinegar to form a thin marinade. Place meat in a 1-gallon re-sealable plastic bag, pour in the marinade and mix thoroughly. Refrigerate for 24 to 36 hours. Longer is better.
Melt butter in large, deep pan and sprinkle with black pepper. Cook on medium for 1 minute. Add onions and cook on high until translucent. Blend in the tomatoes, pepper, and chiles and cook on high until tomatoes have rendered down, about 7 minutes.
Pour in all of the marinade and meat. Bring up to a rolling boil and fold in the mushrooms. Reduce heat, cover, and simmer for 20 minutes. Add the pineapple and sea salt, add hot water if necessary, and simmer another 6 minutes. Serve over a bed of basmati rice and garnish with coriander leaves.
A viewer or guest of the show, who may not be a professional cook, provided this recipe. It has not been tested for home use.