Preparation Steps

• Bloom the gelatin: In a small bowl, sprinkle powdered gelatin over water and let stand 5 minutes.
• Make the pastry cream base: Whisk egg yolks, sugar, and cornstarch in a bowl until smooth. In a saucepan, heat milk with vanilla over medium until steaming. Slowly whisk hot milk into yolk mixture to temper.
• Thicken: Return mixture to the saucepan and cook over medium heat, whisking constantly, until thick bubbles form and it coats the whisk, 2 to 3 minutes. Remove from heat; whisk in butter and the bloomed gelatin until fully melted. Spread into a shallow dish, press plastic wrap directly on the surface, and chill until cool.
• Lighten to Bavarian cream: Whip cold heavy cream to soft peaks. Fold into the cooled pastry cream until smooth. Chill while you make the doughnuts.
• Activate yeast: In a large bowl, combine warm milk, yeast, and 1 tsp of the sugar. Let stand 5 to 10 minutes until foamy.
• Mix dough: Add remaining sugar, eggs, softened butter, and salt. Stir in about half the flour until a thick batter forms, then add remaining flour and mix until a soft dough forms.
• Knead: Turn onto a lightly floured surface and knead until smooth and elastic, 6 to 8 minutes, adding small dustings of flour only if sticky.
• First rise: Place dough in a greased bowl, cover, and let rise in a warm spot until doubled, about 60 to 90 minutes.
• Shape: Roll dough to about 0.5 inch thick. Cut 3 inch rounds and place on parchment squares. Cover and let rise until puffy, 30 to 45 minutes.
• Fry: Heat oil in a deep pot to 350 F. Fry doughnuts in batches, 2 to 3 minutes per side, until deep golden. Drain on a wire rack.
• Fill: Poke a small hole in the side of each doughnut. Spoon the Bavarian cream into a piping bag fitted with a round tip and fill each doughnut until slightly heavy.
• Coat and serve: Toss warm doughnuts in granulated sugar to coat. Serve the same day for best texture.