The CWI Cookbook

 1 lb. potatoes
3/4 oz. onion
2 oz. butter
2 layers of pie crust
Pepper
Salt
4 egg yolks, hard boiled (optional)
1 tbs. mushroom catsup (optional)
Cauliflower (optional)
Tiny onions rolled in curry powder (optional)

Peel and slice your potatoes very thin into a pie-dish; between each layer of potatoes put a little chopped onion (three-quarters of an ounce of onion is sufficient for a pound of potatoes); between each layer sprinkle a little pepper and salt; put in a little water, and cut about two ounces of fresh butter into little bits, and lay them on the top: cover it close with puff paste. It will take about an hour and a half to bake it.
N.B.: The yelks of four eggs (boiled hard) may be added; and when baked, a table-spoonful of good mushroom catchup poured in through a funnel.
Obs.–Cauliflowers divided into mouthfulls, and button onions, seasoned with curry powder, make a favorite vegetable pie.

From The Cook’s Oracle by William Kitchiner MD, New York, 1829

Comment: This is a fairly unusual vegetable pie in that it does not call for any layers of meat products at all. Most that we have seen in books of the time have either complete layers or at least random bits, usually of leftover meat from the previous day, added as flavoring if not a prime ingredient. The final “Obs[ervation]” is somewhat unclear, as we are not sure if Dr. Kitchiner is recommending the cauliflower and/or curried onions as an addition to the potato recipe or as a separate pie of their own. The former seems more probable to us, because if there was a chance to list “Cauliflower and Curried Onion Pie” as a separate entry Dr. K would have almost certainly taken it. He was a somewhat wordy chap.