Heat oven to 350°F. Spray 11x7-inch (2-quart) glass baking dish with nonstick cooking spray. In sprayed casserole, combine potatoes, vegetables and Alfredo sauce; mix well and spread evenly.
Bake at 350°F. for 20 minutes. Meanwhile, make cuts along outside edge of kielbasa at 1-inch intervals, almost but not completely through the other side.
Remove casserole from oven. Place kielbasa on top of potato mixture. Return to oven; bake an additional 20 to 25 minutes or until potatoes are tender and casserole is bubbly.