01 -
Combine flours, sugar and yeast in the bowl of your mixer. Toss in butter chunks, eggs, warm milk, vanilla, and salt. With a dough hook, mix on low for 10 minutes until you get a smooth, slightly sticky ball.
02 -
Form dough into a neat ball, put it in an oiled bowl, wrap with plastic. Let it grow for 2-3 hours until it's three times bigger.
03 -
Flatten dough to ½ inch thick and cut into 3.5-inch circles. Set them on squares of parchment, cover loosely, and wait 1-1.5 hours until they triple in size.
04 -
Beat egg yolks, sugar, vanilla, and lemon zest together. Mix in cornstarch, then slowly pour in warm milk while stirring. Cook gently, always stirring until it gets really thick. Let it cool with plastic touching the surface.
05 -
Warm oil to 170°C/337°F. Cook doughnuts for 2 minutes each side until they turn golden. Let drain quickly, roll in sugar while they're still warm, then cool them before stuffing.
06 -
Cut a small hole in the side of each bomboloni. Squeeze in the cold pastry cream until they're plump. Eat right away for the yummiest taste and feel.