1.   Mix the remaining milk with the cornflour and skimmed milk powder.

2.   Beat in remaining milk, egg, egg yolk, sour cream, and butter.

3.   Add chicken broth and remaining milk.

4.   Add the remaining milk a little at a time, pulsing once or twice after each addition, until the dough holds together in a sticky mass.

5.   Add another cup flour, remaining milk and stir to combine.

6.   Add as much of the remaining milk or stock as necessary to give the mixture a mayonnaiselike consistency.

7.   Add as much of the remaining salt as desired, then add the remaining milk if the potatoes need thinning.

8.   Add remaining milk and adjust salt.

9.   Add remaining milk and beat to desired spreading consistency.

10.   Add remaining milk.