Heat 1-2 inches of vegetable oil in a deep skillet set over medium-high heat to 375°F.
Vegetable oil
While the oil heats, in a separate large saucepan, heat the water, butter, sugar, and salt. Bring to a boil and then reduce heat to low.
1 cup water, ¼ cup unsalted butter, 1 tablespoon granulated sugar, ¼ teaspoon kosher salt
Stir in the flour and stir constantly until combined and mostly smooth. Turn off heat.
1 cup Bob's Red Mill 1:1 Gluten Free Baking Flour
Pour the flour mixture into the bowl of a stand mixer and allow to sit/cool for 2-3 minutes.
Add egg and vanilla and mix on high until smooth.
1 large egg, ½ teaspoon pure vanilla extract
Transfer mixture to a piping bag with a star tip.
Add cinnamon and sugar to a shallow bowl and stir to combine. Line a plate with paper towels. Set aside.
½ cup granulated sugar, 1 teaspoon ground cinnamon
Carefully pipe a 5-6 inch length into the oil, using a sharp knife or scissors to cut off from the star tip.
Allow to fry 2-3 minutes per side, or until golden brown. Transfer to a paper towel-lined plate.
Allow to dry for about 1 minute, then roll in the cinnamon/sugar mixture.
Repeat with the rest of the dough, frying 3 at a time.