|Zwieback slices||70 Gram, coarsely crushed (9 slices)|
|Sugar||2⁄3 Cup (10.67 tbs)|
|Cream cheese||1 Pound|
|Grated lemon peel||1 Teaspoon|
|Lemon juice||1 Tablespoon|
|Eggs||5 , separated|
Place zwieback between layers of waxed paper or aluminum foil and crush with rolling pin; mix with 2 teaspoons of the sugar and the butter.
Work with your hands until ingredients are blended well.
Put zwieback into a 9 inch (23 centimeter) springform pan and press firmly on bottom, using back of tablespoon.
Soften the cream cheese and beat in remaining sugar, a small amount at a time; beat in lemon peel, lemon juice and egg yolks.
Continue beating until fluffy.
Beat egg whites until stiff peaks are formed.
Gently fold into cream cheese mixture until thoroughly blended.
Turn mixture into pan over zwieback crust and bake in a slow oven (300F or 150°C) about 75 minutes, or until filling is "set." Remove from oven and cool on a rack about 10 minutes before removing rim from springform pan.
Allow cheesecake to rest about 3 hours before serving.