From 1922:
Take a neck of mutton, cut it in nice thick cutlets and season; line a fireproof dish with slices of potatoes and fine cut onion, then lay in the cutlets and the potatoes and onions till the dish is full; add then a pint of good gravy, and for the top of the dish slice again potatoes and onions; pour a little warmed butter over the top. Place in the oven; let it get cooked and well browned before sending it to the table. Run off the fat and pour a little rich gravy into the hot pot. An excellent lunch dish.