Season both sides of the steak generously with steak seasoning. (Alternatively cut the steak into bite-sized pieces if you don't desire a specific or more well done temperature)
Preheat a cast iron skillet or nonstick pan on medium high heat. Once hot, add the oil and mushrooms. Saute until golden brown and somewhat soft, then remove from the pan and set aside. Lower the heat to medium, and add in the steak. Cook the steak on both sides getting a nice char all over to your desired temperature using a thermometer (see below). Once done set on a cutting board to rest for 5 to 10 minutes before cutting into bite-sized pieces.
Add the onion, zucchini, and spuash to the pan. Saute until they start to brown then add in the garlic and butter; saute until golden brown. Then remove from the heat. Season with salt and pepper to taste.
In the meantime, in a pot of boiling salted water, cook pasta according to package directions. Reserve 1/4 cup of the pasta water. Drain well and set aside.
Toss the pasta with the vegetables, steak, parmesan, and mushrooms. Serve with bread. Garnish with basil.