Using a food processor or butter knife, cut the butter into the dry ingredients until you have a crumbly consistency. Next, incorporate the water by hand just until you have a smooth dough. Roll into a ball, wrap it in plastic wrap and refrigerate for at least 1 hour.
Spread the pecans on a baking tray lined with baking paper and bake them at 180°C (350°F/Gas 4) for 10 minutes to lightly toast them. Allow them to cool for a few minutes, then crush them coarsely. In a saucepan, heat the sugar syrup, sugar, salt, butter and vanilla. Allow the sugar to dissolve on a low heat, then bring to the boil. Remove from the heat and add the cream. Stir and allow to cool. Add the eggs, one at a time, taking care to whisk the mixture well after adding each egg.
Shaping and Blind Baking
Preheat the oven to 180°C (350°F/Gas 4). If the pastry dough is too hard when it comes out of the refrigerator, let it soften. Butter and flour a 26 cm (10½ inch) pie dish. On a floured surface, roll out the dough to make a round large enough to hang over the edge of the dish by about 3 cm (1¼ inches). Place the round of dough in the dish, then roll the overhang onto itself and pinch with your fingers to stick the dough together. Let it rest in the refrigerator for at least 1 hour. Prick the pastry base with a fork, cover with baking paper and dried beans and bake for 15 minutes. Remove the paper and beans and return to the oven for about 5 minutes until dry and light golden.
Cooking and Serving
Spread the pecans over the baked pastry base and pour over the filling mixture. Place the pie in the oven and bake for about 40 minutes. The filling should be set but still a little wobbly in the centre. When you take it out of the oven, brush the edge of the pastry with sugar syrup. Allow to cool before cutting. Serve with a scoop of ice cream.