Remove crusts from toast. Rinse arugula and dry thoroughly. Peel the bell pepper, remove the seeds, remove ribs and cut into small cubes. Mix sour cream with mayonnaise, bell pepper, shallot and sliced turkey ham and season with salt and pepper.
Chop the arugula coarsely, mix with the turkey ham mixture and distribute over 2 slices of toast. Lay the remaining 2 slices on top and cut diagonally before serving.