Heat a stock pot (or high-sided pan with a cover) over medium-heat, and pour in the oil. When hot, add the mustard seeds and cook for one minute. Stir in the red onion, garlic, and ginger, and cook, stirring often, for 5 minutes. Add the red bell pepper, curry powder, turmeric, ground coriander, and paprika, and, stirring often, cook for one minute, until the spices are fragrant and your kitchen smells like heaven.