Bring a large pot of salted water to a boil (about ½ tablespoon kosher salt for 5-6 quarts water). Put the pasta into the boiling water and cook as the package directions until al dente . Drain, reserving some of the cooking water.
Heat olive oil in a large pan on medium flame. Add chopped garlic and saute for 30 seconds .
Add the sliced mushrooms, red onions, and broccoli. Saute until the veggies are slightly cooked for 2-3 minutes. Turn off flame.
Add the cherry tomatoes and give a stir.
Add the cooked pappardelle pasta and pesto sauce. Add ¼ cup pasta water or more to make a sauce. Gently mix it all together.
Garnish with grated parmesan and fresh basil leaves.