In a large skillet, heat the olive oil and butter until butter is melted. Add the onions and cook until translucent. Add the garlic and cook for 2-3 minutes.
Cut the cream cheese into cubes and add to the skillet. Stir well until completely melted and then add the buffalo sauce, milk and a few dashes of hot pepper sauce to taste. Spoon a small amount of this mixture onto the bottom of a sprayed 9X13 in pan. Stir chicken into the remaining mixture.
Place one layer of cooked lasagna noodles in the bottom of the dish. Spread half of the chicken mixture of the noodles then drizzle with half of the ranch dressing. Add another layer of noodles and then the remaining chicken and ranch dressing. Place a final layer of lasagna noodles and then sprinkle the mozzarella cheese on top.
Bake covered, 350° for about 25 minutes.
Serve with additional ranch or bleu cheese, carrot and celery sticks.