Step 1

Preheat oven to 350 degrees F. Coat a 9- x 13-inch baking dish with cooking spray.

Step 2

In a large skillet over medium-high heat, cook sausage and onion 4 to 5 minutes, or until onion is tender.

Step 3

In a large bowl, combine remaining ingredients; stir in sausage mixture. Transfer to prepared baking dish.

Step 4

Bake, uncovered, for 35 to 40 minutes, or until set and golden. Let stand 10 minutes before cutting.