Step 1

Cut 2 tablespoons unsalted butter into small cubes and let sit room temperature until softened.

Step 2

Heat 6 tablespoons whole milk in the microwave or in a small saucepan over medium heat until warm but not too hot to touch (110°F to 115°F). Sprinkle 1 1/2 teaspoons active dry yeast over the warm milk and let sit until bubbly and foamy, about 5 minutes.

Step 3

Place 1 3/4 cups all-purpose flour, 2 tablespoons granulated sugar, and 1/2 teaspoon kosher salt in the bowl of a stand mixer and whisk until combined. Add the milk mixture, 1 large egg, and 1 large egg yolk. Beat with the dough hook on medium-low speed until a dough forms, about 3 minutes.

Step 4

Add the butter and continue to mix on medium-low speed until all the butter is incorporated, about 1 minute. Increase the speed to medium-high and beat until the dough is smooth and elastic, 4 to 5 minutes more.

Step 5

Lightly coat a medium bowl with vegetable oil and scrape the dough into the bowl. Cover the bowl with plastic wrap or a kitchen towel and let sit in a warm, draft-free spot until doubled in size, about 45 minutes.

Step 6

Lightly dust a work surface with flour. Place the dough on the flour and roll out until 1/2-inch thick. Using a 1 1/2-inch round cookie cutter, cut the dough into as many rounds as you can. Gather and reroll the scraps as needed until you have about 18 rounds. Alternatively, use a tablespoon to scoop the dough then lightly roll each piece into a ball.

Step 7

Heat 4 cups vegetable oil in a large heavy-bottomed pot or Dutch oven over medium-high heat until 350°F. Meanwhile, fit a wire rack over a rimmed baking sheet, or cover the baking sheet with paper towels.

Step 8

Frying in batches of about 5, add the zeppole to the hot oil and fry, stirring with a spider or slotted spoon a few times, until golden-brown and puffed, 3 to 5 minutes. Using the spider or slotted spoon, transfer the zeppole to the baking sheet.

Step 9

Place 2 tablespoons powdered sugar in a fine-mesh strainer and dust the powdered sugar over the zeppole. Serve warm.