Chocolate Pie

This is a small butter cake baked in pie tins, split and layered with frosting — what New England cookbooks called a "pie" long after the rest of the country reserved the word for pastry. The recipe leans on two others in the book, so a few numbers have to be supplied.

• It is a cake, not a pieThere is no crust and no custard. Cakes of this type were commonly baked in round tins of pie-plate size, which is the usual explanation offered for the name. Two 8- or 9-inch layer pans work in the same way.
• OvenBake at 350F. A thin layer of this size sets in about 18 to 22 minutes; test with a skewer at the centre rather than by the clock.
• Method, since it is not givenFollow standard creaming: butter and sugar together, then the egg, then the flour and baking powder alternately with the milk. The butter should be soft, not melted.
• Add saltThe list omits it. With unsalted butter, put in a quarter teaspoon.
• Baking powder strengthTwo teaspoons to 1 1/3 cups flour is generous by modern measure; 1 1/2 teaspoons gives a better crumb and less of a chemical edge.
• Splitting the layersThe recipe does not say how many layers the batter makes; split horizontally, each one yields two thin ones, frosted between and on top of each. Cool completely first -- warm cake tears under a knife. A long serrated blade drawn level across the layer is steadier than sawing.
• The frosting carries the chocolateNothing in the batter is chocolate; all of it comes from the frosting spread between and over the layers, so use a frosting with real body and enough cocoa or melted chocolate to taste.
• YieldOne small cake, roughly eight modest slices. The layers are thin by design and the assembled cake is not tall.