First Step: Prepare the Liquid Base

In a large heavy-bottomed saucepan, combine the whole milk, water, cubed unsalted butter, granulated sugar, optional brown sugar, and kosher salt. Heat over medium-high until just boiling, stirring to fully melt the butter.

Second Step: Make the Choux Dough

Remove the pan from heat and immediately add all the flour at once. Stir vigorously with a wooden spoon or spatula until the mixture comes together into a thick dough. Return the pan to medium heat, stirring constantly for 2 to 3 minutes until dough pulls away from the pan and forms a smooth ball.

Third Step: Cool and Beat in Eggs

Transfer the dough to a large bowl and let it cool for about 15 minutes until lukewarm. Beat in the eggs one at a time, mixing well after each addition until you get a smooth, glossy dough. At this stage, add lemon zest if using.

Fourth Step: Chill the Dough

Transfer the dough into an airtight container and refrigerate for at least 1 hour or up to 24 hours. Chilling improves dough consistency and makes piping easier.

Fifth Step: Pipe the Crullers

Cut parchment paper into 3-inch squares. Fit a piping bag with a large open star tip and fill it with the chilled dough. Pipe 3-inch rings or circles on individual squares, joining the ends neatly.

Sixth Step: Fry the Crullers

Heat vegetable oil in a heavy-bottomed pot or deep fryer to 335°F–350°F (170°C–175°C). Carefully lower 2 or 3 crullers (with parchment paper) into the oil. After about 1 minute, remove and discard the parchment. Continue frying crullers for 2–3 minutes per side until golden and crisp. Avoid overcrowding to keep oil temperature stable.

Final Step: Drain and Glaze

Remove crullers using a slotted spoon and drain on a wire rack. Prepare glaze by whisking powdered sugar, maple syrup, salt, and milk until smooth. Dip warm crullers briefly in glaze, place back on rack to set. Serve immediately for best texture.