While the pasta is cooking, slice the zucchini into quarters, then slice them so you have "triangle" pieces.
Mix the dressing of a balsamic vinaigrette (or mix oil and balsamic vinegar) with dijon mustard, add a pinch of dry oregano, salt, and pepper.
When pasta is done, rice in cold water until pasta is cold.
Allow pasta to drain well, then toss with dressing, then add in the zucchini and onion.
Refrigerate until all chilled, add more balsamic vinegar so it's not dry, mix well.
Top with diced fresh mint and grated cheese and serve.