Cook bacon in a 12-inch heavy skillet over medium heat, turning occasionally, until crisp. Drain on paper towels; discard drippings from skillet.
Meanwhile, cook fusilli in a pasta pot of boiling salted water (3 tablespoons salt for 6 quart water) until al dente. Reserve 1/2 cup pasta-cooking water, then add vegetables to pasta in pot and cook, partially covered, 2 minutes (water will stop boiling). Drain.
Add pasta with vegetables to skillet along with pesto and 1/4 cup reserved cooking water and toss. Season with salt and moisten with additional cooking water if necessary.
Top with crumbled bacon and a generous amount of freshly ground pepper.
