Coat a 9-inch round pie plate or pan with butter. Preheat the oven to 375°. Wash and peel the potatoes, and slice into 1/8 inch rounds. Wash the tomatoes, slice into 1/4 inch rounds, and set aside. Blanch the potato slices in boiling water for 5-7 minutes, stirring occasionally. Immediately rinse in cold water to stop the cooking. Drain completely. In a large mixing bowl whisk together the milk and sour cream. Whisk in the Italian seasoning, salt, pepper, nutmeg, and half of the parmesan cheese. Gently toss the potatoes in the sour cream mixture.

Pour 2/3 of the potato mixture into the pan. Arrange the remaining 1/3 of the potato mixture on the top, alternating in a circle with the tomatoes. There may be some of the mixture left in the bottom of the bowl. If so, pour it over the top of the arranged potatoes and tomatoes. Sprinkle the remaining parmesan cheese over the top, and place the pie plate onto a sheet pan. Bake for 50 minutes at 375°. Change the oven setting to broil at 400°, making sure that the pan is on the top level of the oven. Broil for 10-15 minutes, or until golden brown on top. Enjoy immediately.