Bring a medium pot of water to a boil. Add the pasta and cook according to package directions. About 30 seconds before the pasta is done, add the broccoli florets and corn kernels. Cook for 30 seconds and then drain into a colander. Run cold water over the pasta to stop the cooking. Keep the pasta draining in the colander while you make the dressing.
Whisk together the garlic, red wine vinegar, olive oil, 1/2 teaspoon salt, and a few grinds of black pepper.
Add the well-drained pasta, broccoli, and corn to the bowl, along with the ham, cheese, tomatoes, parsley and scallions, if using. Toss together. Refrigerate in an airtight container for up to 5 days.