- 1 cup whole milk
- 2 tablespoons granulated sugar
- 1 teaspoon salt
- 1 (1/4-ounce) package active dry yeast (2½ teaspoons)
- 2 tablespoons warm water
- 3½ to 3¾ cups all-purpose flour plus additional for dusting
- 10 cups vegetable oil
- 2 large eggs, lightly beaten
- ½ cup Bonne Maman Wild Blueberry or Blackberry Preserves
- Confectioners sugar for dusting
- 1 2½-inch round cookie cutter
- 1 deep-fry thermometer
Bring milk to a simmer in a 1-quart heavy saucepan, then remove from heat and stir in granulated sugar and salt. Cool milk to lukewarm (about 90°F).
While milk is cooling, dissolve yeast in warm water in a small bowl, stirring until creamy, then let stand until foamy, about 5 minutes.
Pour milk mixture into a large bowl and with a rubber spatula, stir in 2½ cups flour, 2 tablespoons oil, eggs, and yeast mixture with a wooden spoon to make a very soft dough.
Spread 1 cup flour on work surface and put dough on top, scraping it from bowl with a rubber spatula. Knead dough, incorporating all of flour from work surface and adding just enough additional flour (if necessary) to keep dough from sticking, until smooth and elastic, 5 to 8 minutes. (Set a timer for this because it’ll seem like an eternity but it is a super important part of the process.)
Transfer dough to another large bowl and sprinkle lightly with additional flour, then cover bowl with a clean kitchen towel and let dough rise in a warm draft-free place until doubled in bulk, about 1½ hours.
Turn out dough onto a floured surface and roll out with a floured rolling pin until ½ inch thick.
Cutout rounds with 2-inch cutter. Stretch 1 round to 2½ inches and put 1 teaspoon jam in center, then stretch another round to 2½ inches and use it to cover jam, pinching edges of rounds firmly together.
Cut through filled doughnuts with floured 21/2-inch cutter, rotating cutter several times to help seal edges. Transfer rounds to a floured kitchen towel, then reroll scraps (only once) and make more jelly doughnuts in same manner. Cover doughnuts with another kitchen towel and let rise in a warm place 30 minutes.
While doughnuts rise, heat 3 inches oil in a deep 4-quart pot until it registers 375°F on your very important thermometer. Fry doughnuts 2 at a time, turning occasionally, until puffed and golden brown, about 2 minutes per batch.
Transfer as cooked to paper towels to drain. While still warm, toss them in a mixture made of your cinnamon and sugar. You can also skip this and dust them with confectioner’s sugar.