4 1/2 C all-purpose flour, divided
1 C milk, warmed, divided
1 1/2 oz. yeast
1 tsp salt
6 Tbsp butter, melted
1/3 C sugar
1/2 lemon peel, grated
5 egg yolks, beaten
shortening or vegetable oil (for deep frying)
raspberry jam or preserves
powdered sugar, as needed
Soften yeast by soaking in 1/4 C of warmed milk. Set aside.
Heat remaining milk to lukewarm. Combine with 2 1/2 C flour, creating a smooth mixture.
Combine yeast and flour mixtures. Cover with a towel and allow mixture to rest in a warm place for 30 minutes.
Mix in salt, knead the dough, and cover for another half hour.
Once doubled in size, combine with melted butter, lemon peel, sugar, egg yolks, and remaining flour.
Lightly flour work surface. Roll out dough to 3/4 inch thick. Cut out doughnuts with a 3 inch round cookie cutter or a glass/cup.
Spread a heaping tsp of jam on half of the rounds. Cover with the other half, crimping the edges. Cover the doughnuts once more, with a towel, for 15 minutes.
Heat oil to 350 F degrees, in a large saucepan or deep fryer. Fry a few at a time, letting each side brown for 2-5 minutes before flipping.
Place on brown paper bags, or thick paper towels, to drain. Roll in powdered sugar, or sprinkle some on top, while still hot.