=== CRUST ===
 1 1/2 c  All-purpose flour
   3/4 c  Unsalted butter; cut into
          -quarters
   1/4 c  Sugar
     1 pn Salt
     1 lg Egg; lightly beaten with
     1 tb Ice water
          === FILLING ===
     4 lg Eggs; separated
   2/3 c  Sugar
    12 oz Ricotta cheese; drained if
          -watery
     2 tb Grated lemon rind
     3 tb Lemon juice
     4 ts Potato starch
     1 ts Vanilla extract
 Make the crust. In a food processor combine the flour, butter, sugar and
 salt and process until mixture resembles coarse meal. With the motor
 running add the egg mixture and pulse just until dough is formed. Wrap in
 plastic wrap and chill 30 minutes. On a lightly floured surface roll out
 the dough into a round 1/8-inch thick and fit it into a 10-inch tart pan,
 pressing edge to 1/2-inch above the rim. Chill until ready to use. Preheat
 oven to 350 degrees. Make the filling. Using an electric mixer beat the egg
 yolks until combined. Add 1/2 cup sugar a little at a time and beat until
 lemon colored. Pass the ricotta through a fine sieve into a bowl. Add the
 ricotta, potato starch, lemon rind and vanilla to the egg mixture and beat
 until just combined. In another bowl with an electric mixer beat the egg
 whites until they form soft peaks. Add the remaining sugar a little at a
 time and beat until firm. Stir 1/4 of the whites into the batter and fold
 in the remaining whites gently but thoroughly. Pour mixture into chilled
 tart shell, place on a baking sheet and bake for 35 to 40 minutes or until
 golden brown and set. Let cool to room temperature and chill 3 hours or
 overnight. This recipe yields ?? servings.
                 
                 Yields       
                1 servings