1.   Add remaining whites and fold in.

2.   Add the remaining whites to the cheese mixture and gently fold until blended.

3.   Alternate the remaining white and sweet potatoes for the top layer, overlapping the slices slightly.

4.   Carefully fold in the remaining whites until smooth.

5.   Fold in remaining whites.

6.   Fold in the remaining whites.

7.   Fold one third of the egg whites into the yolks, then fold in the remaining whites.

8.   Gently fold in remaining whites, taking care not to deflate the batter.

9.   Gently fold remaining whites into puree.

10.   Gently fold in the remaining whites in two additions.