1. Mix the sugar, salt, and yeast in a bowl with a mixer.
2. Whisk in the milk (lukewarm) and eggs, then stir in the lemon zest and knead by hand for about 7-8 minutes. (If you have a kneader, use it)
3. Add the room temperature butter and knead for about 10 minutes to form a smooth dough.
4. Place in a bowl, cover with plastic wrap, and let the dough rise until it has more than doubled in size, about 1 hour.
1. Add the sugar and vanilla bean paste to the egg yolks and whisk to combine.
2. Add the cornstarch and mix evenly, then add the lemon juice and lemon zest.
3. Whisk in the warm milk, then heat to a simmer over low heat.
4. Stirring constantly, boil a little longer and remove from heat when large bubbles appear.
5. Add the butter and melt, stirring to combine and sift through a sieve.
6. Cover the top with plastic wrap to keep air out and chill in the refrigerator.
7. Take out the fermented dough, press it down to release the gas and divide it into 12 pieces.
8. Shape into balls, cover with plastic wrap, and let rise for about 15 minutes.
9. Punch down the dough, shape it into a ball, place it on a piece of parchment paper and cover with plastic wrap.
10. let the dough ferment until doubled in size (about 40 minutes) and fry in oil at 180 degrees.