Prepare Pastry Shell. Combine flour, sugar and salt in food processor.
Whirl to blend. Drop in butter; pulse 3 or 4 times.
Add the shortening and process until the mixture resembles coarse crumbs.
With the machine running, add the ice water, 1 tablespoon at a time. When
the mixture forms lumps, remove the dough from the work bowl and
quickly press into a patty.
Cover the dough with plastic wrap and
chill for 30 minutes. Heat oven to 400 degrees F.
Roll dough out into an 11-inch circle. Ease into a 10-inch tart
pan with removable bottom. Trim the edge. Prick the bottom all over
with a fork.
Bake the shell for 15 to 20 minutes or until golden. Let cool.
Prepare Tart Filling. Combine lemon zest, lemon juice, butter, eggs,
yolks and sugar in a heavy enamel saucepan. Cook the mixture over
low heat, whisking constantly, until slightly thickened. Do not
let boil. remove from heat.
Sprinkle gelatine over the cold water
in 1-cup glass measuring cup. Let stand for 2 minutes for gelatine to
Place cup in small saucepan of simmering water, stirring gelatine
occasionally to dissolve, about 2 minutes.
Stir gelatin into lemon
mixture until well blended.