Preheat the oven to 400°F (200°C).

Place flour in the bowl of a food processor, and add the butter (cut into 16 pieces). Feel free to add a pinch of salt, if you like. I do sometimes, but generally not with fruit desserts.

Pulse 10 times, then sprinkle with the water. Process until it forms a ball.

Roll the dough to 1/8-inch thick.

Cut out four 6-inch circles of dough. Place each circle into a 4-inch tart pan with removable bottom.

Fold edges down and press into the sides of the pan. Trip tops, if necessary.

Spread 1 tablespoon of apple cider or jam evenly onto each crust.

Peel, core apple, and quarter the apple.

Cut each quarter into 7 even slices. Arrange 8 slices onto the top of each crust in a shingle pattern.

Sprinkle each with 1/4 teaspoon of superfine sugar.

Bake for 30 minutes, until the apple cider (or jam) is bubbling away under the apples.

Let cool on a rack and then remove from the tart pan.

Serve each tart with a scoop of vanilla ice cream, if desired.