Sprinkle cooked ham and chopped onion evenly down the center of each tortilla, top each with 2 Tbsp. shredded cheese. Foll up tortillas and place seam side down in a lightly greased 13 x 9 baking dish

Whisk together eggs and next 3 ingredients in a large bowl. Pour mixture evenly over tortillas.

Cover and chill at least 8 hours. Remove from refrigerator and let stand 30 minutes at room temperature before baking.

Bake, covered, at 350, for 20 minutes, uncover and bake 15 more minutes. Sprinkle with remaining 3/4 cup of Cheese and bake 3-4 more minutes. Let stand 10 minutes before serving.