The recipe uses 3 eggs for volume, separated, yolks and sugar whipped over hot water until triple in volume, whites whipped to stiff peaks. Ground walnuts, 2 tbsp breadcrumbs, 1/4 c butter are all folded in. baked at 350 for 40 minutes.
During baking it looks great, rises and is perfection. On cooling the center starts to fall, then the sides turn into the center.
How do you stop it falling? Am i overwhipping?