Start by bringing a large pot of salted water to a boil. Cook the elbow pasta according to the package instructions until al dente. Drain and set aside.
While the pasta is cooking, preheat a grill or grill pan over medium-high heat. Slice the zucchini lengthwise and brush with a little olive oil. Grill the zucchini for about 3-4 minutes on each side until tender and grill marks appear. Remove from the grill and let cool before slicing into half-moons.
In a large bowl, whisk together the remaining olive oil, red wine vinegar, dried oregano, grated garlic, and black pepper. Adjust the seasoning with more salt if needed.
Add the cooked pasta, grilled zucchini, cannellini beans, quartered grape tomatoes, diced red bell pepper, and torn basil leaves to the bowl. Toss everything together until well combined.
If using, fold in the diced aged Italian sausage and sprinkle the shredded parmesan cheese on top. Serve immediately or refrigerate for later.
