Mix the flour with the yeast.
Place 1/4 liter of water, the butter, a lemon peel and 5 g of salt in a pot.
When it comes to a boil, remove the lemon peel and add all the flour and stir until a thick dough forms.
Remove from heat. Let stand for about five minutes.
Add one egg and mix with the wooden spatula until the dough thickens again.
Add the second egg and repeat successively until all four eggs have been added.
Using two spoons, form small balls and fry them over medium-low heat in a pan with plenty of oil until they float. Use only small portions because the dough will rise a lot.
When the fritters are golden brown, remove them to a paper towel and, without letting them cool, dip them in the sugar and place them on another plate or tray. If they were cool, the sugar wouldn't stick to the fritters.
Once they have cooled, they can be filled with pastry cream or whipped cream.
