1In a bowl, mix the flour, a pinch of salt, and butter to form a crumb.
2Gradually, add water and mix with your fingers to get a smooth dough ball.
3Divide the dough into 4 smaller balls and flatten each one with the palm of your hand.
4Cover in plastic wrap and refrigerate for 2 hours minimum.
5Preheat the oven to 430. FLine 2 baking sheets with parchment paper.
6Remove the dough from the refrigerator, and wait 6 to 7 minutes before working.
7Roll out the dough on a floured surface to a 3 millimeter thick circle about 20 centimeters in diameter.
8Place the fruit in the center. Leave about 4 centimeters of empty space at the edge. Sprinkle the fruit with 3 tablespoons of sugar.
9Fold the uncovered portion of the circle on top of the fruit to form a thick edge.
10Brush the edges of the circle with the egg yolk diluted with 1 tablespoon of water.
11Sprinkle with the remaining 3 tablespoons of sugar.
12Bake for about 40 minutes until the edges are lightly browned.
13Whip the cream by mixing it with the powdered sugar.
14Gently mix the lavender flowers with the cream.
15Let the tarts cool for 5 minutes.