In a medium saucepan, combine the water, butter, and salt. Bring to a boil over medium heat, stirring occasionally until the butter is melted.

Once boiling, remove the saucepan from heat and quickly stir in the flour until the mixture forms a ball and pulls away from the sides of the pan.

Allow the dough to cool for about 5 minutes. Then, add the eggs one at a time, mixing well after each addition until the dough is smooth and glossy. Stir in the vanilla extract and cinnamon, if using.

Transfer the dough to a piping bag fitted with a large star tip.

Heat about 2 inches of vegetable oil in a deep pot or fryer to 350°F.

Pipe 4-inch rings of dough into the hot oil, cutting the end of the dough with scissors. Fry in batches, being careful not to overcrowd the pot. Cook for about 2-3 minutes per side or until golden brown.

Remove the crullers with a slotted spoon and drain on paper towels.

For a simple glaze, whisk together 1 cup powdered sugar, 2 tablespoons milk, and 1/2 teaspoon vanilla extract in a bowl. Dip the warm crullers in the glaze and let them set on a wire rack.