Bring a large pot of water to a boil with a pinch of salt. Quarter the squash lengthwise, then slice into 1/4-inch pieces widthwise. Halve the grape tomatoes. Strip the thyme leaves off the sprig, then finely chop. Halve, peel, and thinly slice the red onion. Core, seed, and remove the white ribs from the bell pepper, then thinly slice.

Heat 1 tablespoon olive oil in a large pan over medium heat. add the red onion and season with salt and pepper. Cook, stirring, for 5-7 minutes, until softened and lightly browned.

Meanwhile, add the fusilli to the boiling water. Cook for 9-10 minutes, or until al dente. Reserve 1/4 cup pasta water, then drain.

While the pasta cooks, add the bell pepper, squash and thyme to the pan with the onion and season with salt and pepper. Cook, tossing frequently, for about 8-9 minutes, until the squash begins to brown.

Add the tomatoes to the pan and cook, stirring occasionally, fro 1-2 minutes, until softened.

Add the drained pasta to the pan with the veggies. Toss in half the Parmesan, another 2 tablespoons olive oil, and a splash of pasta water. Season with salt and pepper.