1-First Step: In a bowl, whisk together the 5 large egg yolks, 1 1/2 cups whole milk, and 1/2 cup strong coffee until they’re well combined and smooth.

2-Second Step: In a saucepan, whisk the 3/4 cup granulated sugar, 1/4 teaspoon salt, and 1/4 cup cornstarch to mix them evenly.

3-Third Step: Gradually whisk about 3/4 cup of the egg mixture into the saucepan to temper it, then add the rest of the egg mixture and the 3 tablespoons butter.

4-Fourth Step: Heat the saucepan on medium, whisking constantly until it boils, then let it boil for 1 minute to thicken properly.

5-Fifth Step: Strain the custard into a bowl right away, cover it directly with plastic wrap, and chill it in the fridge until it’s cold and ready to use.

6-First Step: Dissolve the 1 package active dry yeast in 1/4 cup lukewarm water (around 110 degrees F) along with 1 teaspoon of sugar, and let it sit for 10 minutes until it’s foamy and active.

7-Second Step: Heat 1 cup whole milk, 1/4 cup shortening, 1/4 cup granulated sugar, and 1 teaspoon salt in a pan until it’s almost bubbling, then cool it to lukewarm so it doesn’t kill the yeast.

8-Third Step: Combine the milk mixture with the yeast, 3/4 cup mashed potatoes, and 2 large beaten eggs in a bowl, stirring everything together until it’s blended.

9-Fourth Step: Add 5 cups all-purpose flour and stir until the dough comes together, then knead it on a floured surface until it’s smooth and elastic, which takes about 5-10 minutes.

10-Fifth Step: Coat the dough with 1 tablespoon canola oil, cover it, and let it rise in a warm spot until it’s doubled in size, roughly 1.5 hours.

11-Sixth Step: Roll the dough out to about 1/2 inch thick, cut it into 3-4 inch rounds with a cutter, place them on greased sheets, cover, and let them rise again until doubled, about 30 minutes.

12-Seventh Step: Heat 3 cups canola oil in a deep pan to 350 degrees F, then fry the donuts in small batches, 1-2 at a time, for 2 minutes per side until they’re golden brown, and drain them on a wire rack.

13-First Step: While the donuts are still warm, toss them in a mixture of 1/2 cup granulated sugar and 2 teaspoons cinnamon for that perfect coating.

14-Final Step: Once cooled a bit, use a 230 Bismarck tip to pipe the chilled coffee custard into the centers of the donut until they’re slightly puffed, then serve them up for a delightful treat that serves about 13 people.