Step 1: Prepare the Dough

1. In a large bowl, whisk together 2 cups of flour, sugar, yeast, baking soda, and salt.
2. In a separate bowl, combine the warm buttermilk, melted butter, egg, and vanilla extract.
3. Pour the wet ingredients into the dry ingredients and mix until combined.
4. Gradually add the remaining cup of flour until a soft, slightly sticky dough forms.
5. Knead the dough on a floured surface for 3-4 minutes until smooth and elastic.

Step 2: Let the Dough Rise

1. Place the dough in a lightly oiled bowl and cover with plastic wrap or a clean kitchen towel.
2. Let the dough rise in a warm place for 1-2 hours, or until doubled in size.

Step 3: Shape the Beignets

1. Turn the dough out onto a well-floured surface and roll to 1/2-inch thickness.
2. Using a sharp knife or pizza cutter, cut the dough into 2-inch squares.
3. Place the cut dough on a floured baking sheet and cover loosely with a towel.
4. Allow to rest for 30 minutes while you prepare for frying.

Step 4: Fry to Golden Perfection

1. In a deep, heavy-bottomed pot or Dutch oven, heat 2-3 inches of oil to 350°F.
2. Carefully drop 3-4 beignets into the hot oil, being careful not to overcrowd.
3. Fry for 1-2 minutes per side, until golden brown and puffed.
4. Remove with a slotted spoon and drain on paper towels.

Step 5: Glaze or Dust with Sugar

1. For glazed beignets: Mix powdered sugar, milk, vanilla, and salt until smooth.
2. Dip each warm beignet into the glaze, allowing excess to drip off.
3. Place on a wire rack to set.
4. For traditional beignets: Place warm beignets in a paper bag with powdered sugar and shake gently to coat.