Preheat oven to 350 degrees. Press the potatoes between paper towels to remove any excess moisture. Mix the potatoes, butter, salt and pepper in a bowl. Pat the potato mixture over the bottom and up the side of a greased 9 inch pie plate and bake for 20-25 minutes or until light brown. Maintain the oven temperature.
Heat the oil in a skillet and add the bell pepper and onion. Saute until tender and remove from the heat. Stir in the beans, corn, jalapeno chiles, cumin and chili powder. Fold in the cheese and cilantro. Spoon the bean mixture into the potato crust and bake for 20 minutes. Cool in the pie plate on a wire rack for 10 minutes.
Mix the sour cream, lime juice, salt and pepper in bowl. Top the tart with the topping and garnish with the cilantro.