Preheat the fryer. In a mixing bowl, combine the confit, 1 cup of the mayonnaise and red onions. Mix well. If the salad is too dry, add more mayonnaise. Season with salt and pepper. Spread 1 cup of the salad evenly over 6 slices of the bread. Season both sides of the tomatoes with salt and pepper. Lay 2 slices each of the tomato and cheese over the duck salad. Place the remaining slices of bread over the cheese. Press each sandwich together. Fry the potatoes, in batches, until golden brown, about 4 minutes, stirring occasionally. Remove and drain on paper towels. Season with salt. Slice each sandwich in half diagonally and serve with the Sweet Potato Chips.