Preheat your oven to 400°F (200°C) and line two baking sheets with parchment or foil. Place the butternut squash in a mixing bowl and toss it with 1 tablespoon of the neutral oil, then transfer it to one of the baking sheets. Toss the zucchini pieces with the remaining tablespoon oil, then transfer them to the other baking sheet. Season the squash and zucchini with kosher salt and freshly ground pepper to taste, then transfer both baking sheets to the oven. Roast the zucchini for 25-30 minutes, or until tender and browning. Roast the squash for 40 minutes, or until the squash is fork tender and browning at the edges.
While the vegetables roast, make the pesto. Place all ingredients into a food processor and process till the pesto is relatively smooth, but some pieces of the seeds are still visible. Taste and adjust salt, pepper, lemon, and nutritional yeast to taste.
Bring a large pot of salted water to a boil. Cook the Chickapea shells according to package instructions. When the pasta is ready, transfer it to a large mixing bowl. Add the roasted butternut squash and zucchini, then the raw arugula. Add the pesto, using just enough to coat all of the pasta and vegetables well (if you have a couple tablespoons leftover, you can save them for topping roasted vegetables, salads, bowls, polenta, or other pasta dishes, or you can freeze them in an ice cube tray!). Taste the pasta salad and adjust salt and pepper as needed. Serve.
Pesto will yield about 3/4 cup/180 milliliters. It can be stored in an airtight container in the fridge for up to 5 days or frozen for up to 6 weeks. Leftover pasta salad keeps well for up to 3 days.