Heat the cheese and milk at 50C (TM #2, 50C, 4 minutes) until the cream cheese is completely dissolved and smooth.
Add the vanilla essence, zest and then the egg yolks, one at a time (TM#1).
Add the lime juice and then sift in the flours (TM#1, 1 minute)
Beat the egg whites, sugar and cream of tartar until stiff peaks are formed (Kitchen Aid #6, 5 minutes)
Fold the egg white mixture into the cream cheese mixture, 1/3 at a time.
Line the tin completely, and allow the sides to be higher than the pan.
Pour the batter into this pan, and level as well as possible.
Put a cookie pan on the lowest shelf in the oven, and pour in boiling water.
Put a shelf just above this cookie pan and the cake tin with the cheesecake batter on this shelf.
Bake at 160C for 15 minutes, then at 140C for 50 minutes, remove the tray of water and bake at 170C for 10 minutes to brown the top. Leave the cake in the oven with the oven door ajar, until the oven temperature reaches around 70C. Remove cake from the oven.
Refrigerate when it has cooled to room temperature, and overnight before consuming for best results.
Sieve some icing above the cake if desired.