Step 1

In a large pot cook pasta according to package directions; reserve 1½ cups pasta cooking water. Drain; set rotini aside.

Step 2

In the same pot, cook Broccolini with ¼ cup of the vegetable broth over medium-high about 3 minutes. Add the next six ingredients (through garlic); cook 5 minutes more or until just crisp-tender, stirring frequently. Remove from heat; add rotini and squash.

Step 3

In a bowl whisk together the remaining ¾ cup broth and the next four ingredients (through mustard). Add to pasta mixture in pot; toss to combine. Add reserved pasta cooking water a little at a time until creamy. Return to heat; heat through. Season with salt and black pepper.