Preheat the oven to 425℉. Spray two 4-ounce ramekins with cooking spray and set aside.: As the oven warms you will notice a dry, anticipatory heat filling the kitchen, which primes the baking environment so the crust begins to set immediately, producing a flakier bottom. Preheating ensures accurate bake times and consistent browning, and spraying the ramekins prevents sticking so the crust lifts out smoothly. A typical error is under heating the oven, which yields a soggy bottom crust, or over spraying the ramekins which can pool and soften pastry edges, so use a light, even coat and wait for the full heat to build.
Combine flour and salt in a small bowl. With a pastry cutter, cut in the shortening until the shortening pieces form small bits. Slowly add in water 1 tablespoon at a time. Knead the dough as little as possible and shape into a large ball. Wrap the ball of dough in plastic wrap and place in the fridge.: Right away you will sense the tactile contrast between flour and cold shortening, and the cutting action should leave pea sized bits of fat coated in flour, which melt in the oven to create flakiness. Adding ice cold water one tablespoon at a time lets you control moisture, bringing the dough together without making it wet. Wrapping and chilling firms the fat, reducing gluten development, and makes rolling much easier. Avoid over kneading, which warms the fat and activates too much gluten, resulting in a tough crust; if the dough feels elastic rather than tender, rest it longer in the fridge.
Peel, core, and chop apples into small pieces and lightly toss them in lemon juice. In the same bowl, add flour, cinnamon, nutmeg, granulated sugar, and brown sugar, stirring until apples are evenly coated with the spiced mixture.: When you cut the apples you will hear a crisp snap and see glistening white flesh, then the lemon juice will brighten the fruit and halt browning. Tossing with the dry mix coats each piece so spices and sugars penetrate during baking, producing a cohesive filling. The tiny grains of sugar begin to draw juice from the apples as you mix, which is why uniform piece size matters for even cooking. A common slip is chopping unevenly, which can leave some pieces undercooked and others falling apart; aim for consistent small dice for uniform texture.
Remove dough from fridge and roll it out. Using the ramekins inverted, cut out 2 circles of dough. Place the circle of dough in the bottom of the ramekins. Rip off some dough and place the dough around the edges of the ramekins. Make sure dough is thin so it cooks properly.: The chilled dough should roll smoothly without tearing, and when you lift the circle it will hold shape, a sign it is properly rested. Inverting the ramekin as a template guarantees a perfect fit, and pressing a thin strip of dough around the rim creates a neat edge that browns attractively. Thin dough cooks evenly and prevents raw pockets; too thick a crust will stay doughy, too thin will crisp and possibly break when filled. If the dough resists stretching, let it rest five to ten minutes to relax the gluten.
Stuff apple filling into ramekins and pack tightly. Cut the 1/2 tablespoon butter into tiny pieces and top the pies equally with butter.: As you fill, the sound changes from dry flour rustle to a moist, compacted mound, and pressing the apples in tightly prevents large air pockets that can steam and create a soggy interior. Dotting with small pieces of unsalted butter lets pockets of richness melt into the fruit, producing glossy, layered flavor. Over packing can force juices up under the top crust and cause leaking, while under packing yields air gaps that collapse during baking; aim for a snug, even fill.
Cover the pie with another circle piece of dough or create a lattice top (see note 1).: A full top will seal in juices and create a classic look, while a lattice allows steam to escape and offers a crisper top texture. If you choose lattice, weaving strips produces visual appeal and more surface area for a crunchy finish after brushing with butter. A mistake here is sealing poorly, which can cause leaking during baking; moisten the rim lightly to help the top adhere and trim excess dough for neat edges.
From the Topping section, melt butter and brush over pies with a pastry brush. Stir together the sugar and cinnamon and sprinkle on top of pies.: Brushing the surface with melted unsalted butter creates a glossy sheen that encourages even browning, and the cinnamon sugar forms a caramelized finish that crackles slightly when the pies are warm. The aroma of butter and cinnamon intensifies as they hit the hot crust, signaling a nearly done bake. Skip the brushing or use too much butter and the topping can pool and burn; aim for an even, light coat and an even sprinkle of the sugar mixture.
Place pies on a sheet pan and bake for 8 minutes at 425℉, then reduce to 350℉ and bake for 25-30 minutes. Cover pies with a foil tent if they brown too much.: The initial high heat gives an immediate lift and fast set to the crust, and lowering the temperature allows the filling to cook through without over browning the top. You will notice the filling begin to bubble at the edges and the crust take on a warm golden color. If the tops brown too quickly, a foil tent protects them while the interior finishes cooking. A common pitfall is skipping the temperature reduction, which can scorch the crust before the apples become tender.
Remove from oven, let cool, and enjoy!: After baking you will see bubbling juices and a deeply golden crust, and letting the pies rest allows the filling to set so slices hold their shape. Cooling also mellows the searing heat of the filling so you can taste the layered spices and butter without burning your mouth. Rushing to cut while piping hot can cause runny filling and burns, so give them time, roughly ten to fifteen minutes, to settle before serving.