Prepare the Pastry Shells:

1. In the bowl of a food processor, combine the flour, icing sugar and salt and pulse to mix. Add the cold butter, and pulse five or six times, until mixture resembles coarse meal.
2. In a small bowl, whisk together egg yolk and vinegar. With the machine running, add egg yolk mixture, then add the ice water, one tablespoon at a time, stopping as soon as the dough starts to clump together.
3. Turn the dough out onto a clean surface, divide in half, and gently form each half into a flat disk. Wrap in plastic, and refrigerate for at least one hour or until quite firm. (You can also do this a day or two in advance.)

Prepare the Filling:

1. While the pastry chills, begin on the frangipane filling.
2. In a large mixing bowl, beat butter and sugar until fluffy. Add the eggs, one at a time, beating well after each addition. Stir in ground almonds, almond extract and vanilla. Cover the bowl tightly with plastic wrap, and chill for 30 minutes.

Assemble the Tarts:

1. Preheat oven to 400F.
2. On lightly floured surface, roll out the chilled pastry to 1/8" thick. Using a 3-inch round cookie cutter, cut out 24 circles. Gently press the dough circles into the cups of a mini muffin tin, then place in the freezer to chill thoroughly for 15 minutes.
3. Spoon 1/2 tsp jam into the bottom of each shell, then spoon in a little frangipane overtop, making sure to leave a little rim of tart shell uncovered. (Make sure not to overfill, as it will be very difficult to extract the tarts once they're baked!)
4. Bake in preheated oven until filling is puffed and golden, about 18-20 minutes. Let tarts cool in pan for about 10 minutes, then carefully remove and set on a wire rack to cool off completely before frosting.

Glaze and Decorate the Tarts:

1. Once the tarts are cooled, whisk together icing sugar, water and almond extract in a small bowl until you have a smooth, thick glaze. Spread a layer of icing onto the cooled tarts, then finish each one with a piece of cherry.