Adding 1/4 cupful at a time, whisk in one - third of hot cream mixture, then whisk egg mixture into
remaining cream mixture in saucepan.
Make a well in the center large enough to hold
the remaining cream mixture.
Gradually whisk in
remaining cream mixture.
Repeat this process with the sweet potatoes, Yukon Gold potatoes and turnips, using 1/3 of
the remaining cream mixture for each vegetable.
Slowly pour the egg mixture back into the saucepan with
the remaining cream mixture, whisking constantly.
Slowly pour the egg mixture back into
the remaining cream mixture in the saucepan, whisking constantly.
Spread
the remaining cream mixture over the top and wrap the edges of the plastic wrap back over the top of the tin to cover.
Pour the egg mixture into the saucepan with
the remaining cream mixture.
Transfer the yolk mixture back to the saucepan with
the remaining cream mixture and return it to medium heat.