As beautiful to look at as it is to taste, this custard tart is easy to make with the help of shortbread cookies. In this recipe, the pears are simply tossed with a bit of sugar, but if you'd like to anty up the flavor, gently poach the pear slices before layering them into the tart crust.
Preheat the oven to 350 degrees.
Place the shortbread cookies in food processor and process until finely ground. Add the egg, melted butter, flour, sugar, salt, and extract, and process again until a soft, buttery dough forms. Remove the dough and roll into a ball. Wrap in plastic and chill in refrigerator for 20 minutes.
Press the chilled dough into 13-by-4-inch rectangular or 9-inch round tart pan and score all over with a fork. Place the tart pan on a baking sheet and blind bake (bake without a filling) in the oven for 7 minutes. Remove and let cool.
Toss the pear slices in a bowl with the cinnamon, sugar, and lemon juice. Set aside.
Combine the butter and chocolate in a small saucepan over low heat, stirring until completely melted. Stir in the milk, almond, and salt. Set aside.
Combine the egg, egg yolk, sugar, flour, and cocoa powder in the food processor or mixer bowl and process for 2 minutes. Pour in the milk and chocolate mixture and continue to process until smooth and completely incorporated.
Arrange the pears in the tart pan, peel side up, and then pour mixture so that it reaches the very top of the crust (depending on the size of your pears, you may have some custard leftover). Bake for 25 minutes at 350 degrees, or until filling is set and crust is slightly golden. Let cool completely before serving.