Doughnuts in Halachah
Do I Have to Wash for Fried Doughnuts?
The brachos recited before and after eating doughnuts fried in oil are mezonos and al hamichyah, respectively. This is because the brachos for any of the five types of grain (wheat, barley, oats, rye and spelt) that are maaseh kedeira (boiled, as opposed to baked) are mezonos and al hamichyah, according to most poskim. The consensus among poskim is that deep frying is halachically the same as boiling in water—it makes no difference whether the food is cooked in water or in oil.
Even if a person is koveia seudah (establishes a meal) on doughnuts alone—as some might do on Chanukah—and they eat kedei seviah (to satiety), the brachos are still mezonos and al hamichyah, and one does not have to wash for hamotzie regardless of how many doughnuts they eat.
The custom is to make a brachah on doughnuts that are served as a snack in middle of a bread meal, or as a dessert at the end of the meal. However, if they're being eaten to satisfy one’s hunger, and not as a snack, they’re considered like any other dish served during the course of a bread meal, and no separate brachah is made.
On Shabbos, one may squeeze out the excess oil from fried doughnuts prior to eating them—if the intent is simply to eliminate the excess oil, and they are not squeezing the doughnuts for the oil. #472
https://halacha2go.com?number=472
https://asktherav.com/article-472-doughnuts-in-halachah/