Heat water in a sizable pot for pasta. Once boiling, add salt and pasta, and cook according to package. When done, strain the pasta, rinse under cold water and return to pot.
Meanwhile, heat a medium-large pan on medium heat and melt butter. Once melted, toss in asparagus and garlic. Cook for 6-8 minutes, turning frequently, until asparagus is bright green and slightly softened. Remove from heat.
Add and stir in cooked asparagus, prosciutto, tomatoes and arugula to the pot of pasta.
In a small bowl, whisk together the lemon juice, olive oil, Dijon mustard, and seasoning.
Mix dressing into pasta salad and toss with parmesan cheese.