Pumpkin Pie with Hazelnut Mousse

In mixing bowl beat egg whites until soft peaks form (tips curl over when beaters are lifted). In small saucepan combine water and sugar; cook and stir over medium heat until sugar is dissolved and mixture comes to a boil. Clip a candy thermometer to side of pan. Cook at a steady boil over medium heat until mixture reaches 240 degrees F (about 5 minutes). Beat egg whites on high speed, slowly pouring in the hot sugar mixture (pour against side of bowl, not in the beaters). When all of sugar mixture is added, continue beating 5 minutes more to cool mixture. In a large bowl whisk together whipping cream and mascarpone cheese; whisk in the Frangelico or other hazelnut liqueur, if desired, and hazelnuts. Whisk in cooled egg whites. Sprinkle with remaining hazelnuts.

In a very large bowl combine flour, sugar, kosher salt,* and baking powder. With a pastry blender cut in butter leaving chunks the size of peas. Combine water, sour cream, and vinegar. Add liquid all at once to the flour mixture. Quickly stir to distribute; do not overmix. The dough should be slightly crumbly. Let rest in the refrigerator for at least 2 hours or overnight. The finished dough should break, not stretch. Divide into three portions; shape into disks. Use at once or wrap and refrigerate up to 3 days. Or freeze up to 1 month. Thaw overnight in the refrigerator if frozen.