Heat olive oil in large heavy saucepan. Add onions and sauté until caramelized, about 15 minutes. Add garlic and sauté 1 minute Add tomatoes, tomato paste, red pepper, curry powder and vegetable stock. Bring to a boil then reduce to a simmer and cook 15 minutes. (Stew may be made up to this point two days ahead. Reheat gently and proceed.) Add the smoked whitefish and simmer for 10 minutes. Stir in kale for last minute of cooking. Season to taste with salt and pepper.
Stay healthy with this fully cooked whitefish stew