All the classic flavor of a Reuben sandwich, but in casserole form! This scoop-able, serve-able version of the deli favorite features rye, corned beef, sauerkraut, Swiss cheese, and a homemade Russian dressing, all in convenient casserole style.
Preheat oven to 375°F. Lightly grease a 13- x 9-inch baking dish with cooking spray. Set aside.
Combine mayonnaise, dill pickle relish, ketchup, lemon juice, Worcestershire sauce, salt, and pepper in a medium bowl. Whisk in eggs and milk until combined.
Stir together corned beef, bread cubes, sauerkraut, and 3/4 cup of the cheese in a large bowl. Top corned beef mixture with egg mixture; stir well to coat.
Transfer corned beef mixture to prepared baking dish. Top with remaining 3/4 cup cheese. Cover with aluminum foil, and bake in preheated oven until eggs are mostly cooked through and cheese is melted, about 20 minutes. Uncover and bake until cheese is golden and bread is toasted, about 20 minutes more. Remove from oven, and let stand 10 minutes before serving.