Bring a large pot of lightly salted water to a boil. Add pasta and cook for 8 to 10 minutes, or until al dente. Rinse under cold water, drain and set aside.
Meanwhile, place eggs in a saucepan and cover with cold water. Over medium heat bring water to a full boil. Lower heat and simmer for 10 to 15 minutes. Immediately plunge eggs into cold water. Let cool completely, then peel and slice.
In a large serving bowl, toss together the pasta, egg, ham, peas and Swiss cheese. In a separate bowl, mix together the mayonnaise, sour cream, spring onion, mustard and Tabasco sauce. Stir until well blended.
Pour 3/4 of the dressing over the pasta and toss to coat thoroughly. Spread the remaining dressing evenly over the top of the pasta salad, all the way to the edge of the bowl. Sprinkle with paprika, cover tightly and chill 4 hours, or overnight for best flavour.