Most people think of oatmeal pies as hand-held sandwich cookies filled with creamy frosting. But this is a pie in the traditional sense, with a buttery crust and a gooey chocolate filling topped off with a layer of golden toasted oats. Long ago, when nuts were either too expensive or hard to come by, oatmeal pies were a thrifty alternative to pecan pies. But this dessert is delicious in its own right, and a real treat for people with nut allergies. Make sure to toast the oats thoroughly on a baking sheet in the oven. The step brings out the oats’ nutty flavor, which pairs so well with the rich, lightly spiced chocolate filling. This pie can be made a day or two in advance. Once it has cooled completely, store it in the refrigerator and let it come to room temperature before slicing and serving. You can also save on prep time and make the pie come together faster by using store-bought refrigerated piecrust instead of homemade.