In Switzerland, this extremely popular salad (Emmenthaler Wurstsalat) is always made with cervelat sausage. Since it's not available here, I use mortadella, which is close in taste and texture. Buy the mortadella at the deli counter and have them cut it into 3/4-inch/ 2 cm thick slice(s).You also can substitute cooked and cooled knackwurst. The sweet pepper is my North American addition; some people add diced boiled potatoes and/or hard-cooked eggs. The egg yolk in the dressing enriches and thickens it; if you have concerns about the raw yolk, you can leave it out. Serve this salad with crusty rye or multigrain bread.