Anglo-Indian Curry Sauce

Preparation : Heat oil in a heavy, medium-sized skillet over medium heat. Add onions and stir-fry until onions turn caramel brown, about 12 to 15 minutes. Remove from heat. Place in a blender with the ginger, tomatoes, cilantro, cayenne and salt; puree until smooth. Transfer to a medium-size saucepan. Stir in garam masala or curry powder, cover, and cook over medium heat until tomatoes loose their raw aroma, 15 to 18 minutes. Makes about 2 cups. Laxmi Hiremath writing in the San Francisco Chronicle, 6/24/92.