Boil pasta shells in salted water until slightly firm, according to package directions.
In another saucepan, combine the vegetable broth, Parmesan, cheddar, and butternut squash over medium heat until melted and combined. Turn off the heat. Add salt, mustard, white pepper, Worcestershire sauce, chili powder & Tabasco.
Drain the pasta but don’t rinse it. Add it to the cheese sauce (use a large bowl if necessary) and toss to coat the pasta. Taste and add more salt or pepper, according to your taste.