Chai Sufganiyot (Hanukkah Donuts) with Orange-Pumpkin Buttercream

Place 2 1/2 cups of flour, the cinnamon, cardamom, and salt in a large bowl and whisk to aerate and combine; set aside. Coat a second large bowl with vegetable oil; set aside.

Place the yeast and 1 teaspoon of the sugar in a medium bowl.

Add the water and stir to combine.

Add the tea bag and let sit until the mixture is foaming, about 5 minutes.

Remove the tea bag, squeeze the liquid from the tea bag back into the bowl, and discard the tea bag.

Add the remaining 1/4 cup sugar, milk, egg yolks, and vanilla and whisk to combine.

Add this mixture to the reserved flour mixture and stir with a wooden spoon until the dough comes together and begins to form a ball.

Transfer the dough to a lightly floured work surface. Scatter the butter pieces over the dough and knead until the butter is fully incorporated and the dough is smooth, shiny, and elastic, about 6 to 8 minutes.

Add up to 1/4 cup of additional flour as needed if the dough is sticky. Form the dough into a ball, place it in the oiled bowl, and turn to coat it in the oil. Cover the bowl with plastic wrap or a damp towel and let the dough rise in a warm place until doubled in size, about 1 1/2 to 2 hours.Line a baking sheet with parchment paper; set aside. Once the dough has risen, punch it down, transfer it to a lightly floured work surface, and roll it out until it’s about 1/4 inch thick. Using a 2-1/2-inch round cutter, stamp out as many dough rounds as possible and place them on the prepared baking sheet about 1/4 inch apart. Gather the dough scraps into a ball and roll out and cut again. Discard any remaining dough scraps.Cover the dough rounds loosely with plastic wrap or a damp towel.

Place the butter, pumpkin, nutmeg, and orange zest (if using) in a medium bowl and whisk until combined.

Add the powdered sugar and whisk until completely smooth and combined.

Place the oil in a Dutch oven or a large, heavy-bottomed pot and set it over medium heat until the temperature reaches 365°F on a candy/fat thermometer. Meanwhile, fit a wire rack over a second baking sheet; set aside.

Place the sugar in a large bowl; set aside.When the oil is ready, add 4 of the dough rounds and fry until golden brown, flipping halfway through, about 2 minutes total. (If air bubbles appear in the donuts, pierce them with the tip of a paring knife.) Using a slotted spoon, remove the donuts to the wire rack.

Add 4 more dough rounds to the oil. While these dough rounds are frying, use tongs to transfer the first 4 (still-hot) donuts into the bowl of sugar. Toss to coat in the sugar, then return to the wire rack. Repeat frying and sugarcoating the remaining dough rounds.When the donuts are cool enough to handle, use a paring knife to puncture the side of each to form a pocket in the center.

Place the tip of the piping bag into the pocket and pipe about 1 heaping teaspoon of buttercream inside.

Serve warm or at room temperature.