Make the pancake: Preheat the oven to 450 degrees F. Mix the granulated sugar, brown sugar and pie spice in a large bowl. Rub a rimmed baking sheet with 2 tablespoons butter and arrange the apple slices on top in a single layer; sprinkle with 1/3 cup of the sugar mixture. Bake until the apples are tender and the baking sheet is mostly dry, 25 to 30 minutes.
Meanwhile, whisk both flours, the baking powder, baking soda and salt into the remaining sugar mixture. Whisk the milk, yogurt, eggs and vanilla in a separate bowl. Stir the milk mixture into the flour mixture.
Pour the batter over the apples and gently spread to cover. Bake until dry on top and a toothpick inserted into the center comes out clean, 12 to 15 minutes. Brush with the remaining 1 tablespoon butter. Let cool 15 minutes.
Make the glaze: Stir the confectioners' sugar, cider and pie spice in a bowl. Drizzle over the pancake. Cut into squares, invert onto plates and serve with maple syrup and/or whipped cream.