Preheat oven to 400°F. Line two baking sheets with parchment paper or Silpat baking sheet.
Add the flour, sugar and taco seasoning to the bowl of a food processor and pulse to combine. Cut the butter into small pieces and add it to the food processor. Pulse until the mixture resembles coarse sand. Add the water and vanilla and pulse until a smooth dough forms. Add more water if needed for dough to come together. Do not over-process.
Divide the dough into 4 pieces. Move one piece of dough to your work surface and keep the others covered with a towel to prevent them from dying out. Lightly flour your work surface and rolling pin and roll the dough into a large rectangle.
Roll as thin as possible. Use a pizza cutter to cut the rectangle into squares about 1 to 1 1/2 inches wide.
Transfer the dough squares to the prepared baking sheets. They won’t spread so they can be placed close together. Sprinkle the squares with salt. Repeat the rolling and cutting process with the other 3 pieces of dough. Stick your scraps under the towel and roll them out last for one last batch.
Bake the crackers until crisp and brown or about 5-10 minutes. Watch closely to prevent burning. Once baked, transfer to a plate to cool. Store the crackers in an airtight container.
Have additional flour on hand for for rolling out crackers.
Your number of crackers may vary depending on how thin or thick you roll the dough.