Step 1

In a large, heavy bottomed saucepan, bring the milk, water, butter, sugar and salt to a rolling boil over medium heat. (A rolling boil means that bubbles are "rolling" across the entire surface of the liquid.)

Step 2

Remove from the heat and add the flour all at once. Stir vigorously with a wooden spoon until combined and throughout moistened.

Step 3

Return the pan to the heat and cook for 2-3 minutes, stirring vigorously the entire time. The dough will be very thick and stirring it will give your arm a good workout. Rather than "stirring", think of it as kneading the dough with a wooden spoon. After 2-3 minutes, a thick film should have formed over the bottom of the pan and the dough should feel smooth.

Step 4

Dump the dough into the bowl of an electric standing mixer and use the spoon to spread it out into a somewhat thin layer, covering the bottom of the bowl and moving a few inches up the sides. Let cool, uncovered, until the dough is just slightly warm - about 15 minutes.

Step 5

Fit the mixer with the paddle attachment, scrape down the sides of the bowl with a rubber spatula, and add 2 of the eggs to the dough. Beat on medium speed until the eggs have been fully incorporated into the dough, stoping to scrape down the sides of the bowl as necessary.

Step 6

Scrape down the sides of the bowl and add the 3rd egg to the dough. Beat on medium until fully incorporated. Scrape down the sides of the bowl and add the egg white and lemon zest. Beat on medium until fully incorporated.

Step 7

Scrape down the sides of the bowl, cover and let chill in the refrigerator for 10 minutes.

Step 8

Cut out ten 3-inch by 3-inch squares of parchment paper and brush each lightly with vegetable oil.

Step 9

Heat a fryer to 370 degrees. OR - add enough vegetable oil to a deep saucepan or stockpot to come 3 or 4 inches up the sides, and heat the oil to 370 degrees. (It's extremely helpful to have a deep fry thermometer.)

Step 10

Remove the dough from the refrigerator and scoop some into a pastry bag fitted with a large star tip. Holding the pastry bag vertically over one of the parchment squares, pipe an even circle of dough, just making the ends meet and connect. Repeat with the remaining dough and parchment squares.

Step 11

Gently place a cruller onto a slotted spoon, along with it's paper, and lower it into the hot oil, paper and all. Hold the spoon under the cruller for 4 or 5 seconds to prevent it from sinking to the bottom of the fryer. Fry the doughnuts 3 or 4 at a time for 5 1/2 to 6 minutes, removing the paper with mental tongs after 1 minute and flipping them over after 2 1/2 minutes. The crullers should be a deep golden brown on all sides. Do your best as the dougnnuts cook to keep the temperature of the oil between 355 - 370 degrees.

Step 12

Use a slotted spoon to remove the doughnuts from the oil to drain on paper towels. Cool completely before glazing.

Step 13

Add all glaze ingredients to a small bowl and stir to combine. Add enough milk to create a runny glaze that's still thick enough to adhere to the tops of the doughnuts.

Step 14

When the crullers are completely cool, dip the tops of each one into the glaze.