How to make
Sift the flour and powdered sugar, add the butter and mash it. Add the egg yolk, sugar and baking powder, stir.
Knead lightly with your fingertips and add the water. Add the vanilla and knead a hard dough, leave it to rest. Roll it out and sprinkle with flour.
Transfer the rolled out dough into a buttered baking form and form an edge. Pierce the pie crust in several spots and bake in a preheated 360°F (180 °C) oven for 10 min. or so.
Caramelize the sugar and add the walnuts. Pour in the slightly heated cream and stir well. Remove from the stove. Distribute the filling over the baked crust and let it cool before serving.
