Preheat oven to 400°. Sauté ham in hot oil in a large skillet over medium-high heat 5 minutes or until browned. Stir in collards and onion, and sauté 5 minutes or until onion is tender and liquid evaporates. Layer half of collard mixture in a lightly greased 9-inch pie plate; top with ¾ cup cheese. Repeat layers once.
Whisk together milk and remaining ingredients until smooth; pour over collard-and-cheese mixture in pie plate.
Bake in preheated oven 25 to 35 minutes or until a knife inserted in center comes out clean. Let stand 10 minutes before serving.
