Indian Chicken Curry

2 teaspoons curry powder

2 teaspoons chili powder

1 teaspoon salt

1 teaspoon ground coriander

1 teaspoon ground ginger

1 teaspoon ground cumin

1 teaspoon ground cinnamon

3 tablespoons butter

1 cup chopped onion

2 cloves garlic , minced

1 lb boneless skinless chicken breast , cut into 1 inch pieces

1 (8 ounce) carton plain fat-free yogurt

1 (6 ounce) can tomato paste

5 cups cubed peeled baking potatoes

4 cups water