In a medium bowl, whisk together the whole wheat flour and the sea salt. Add the sourdough starter, olive oil and nutritional yeast. Stir to bring the ingredients together to form a dough. I love using this Danish dough whisk.
Divide the dough in half. Shape each half into a rectangle. Wrap each rectangle in either parchment paper or plastic wrap. Refrigerate for at least 30 minutes or even overnight.
Preheat your oven to 350 degrees F.
Remove just one block of dough from the fridge. Place it on a lightly floured piece of parchment, cut to the size of your baking sheets. Flour your rolling pin and begin rolling the dough out, rotating the sheet of paper with every few rolls. Roll the dough out to about 1/16th of an inch. The edges will be a bit rough…that's fine. Those bits are perfect for testing and snacking.
Carefully move the parchment, with the rolled out dough, onto a baking sheet. Brush the top of the dough very lightly with some additional extra virgin olive oil, then lightly sprinkle a bit of coarse sea salt and nutritional yeast on top. Using a pizza cutter, cut the dough into about 1 1/2 inch crackers. You can do this freehand, or use a ruler to get them nice and square. Either poke a hole into each cracker's center with a wooden skewer or use a fork to prick the tops.
Repeat the rolling, cutting and poking with the remaining block of dough.
Bake the crackers for 10 minutes, then rotate the baking sheets and switch them from top to bottom to be sure they bake evenly. Bake them for an additional 10 minutes or more. You'll find that depending on how thick the dough has been rolled, you'll have to adjust baking time to get the perfect crunch. Keep in mind, the crackers will crisp up as they cool. You want the crackers to get a bit golden brown, but be sure not to burn them.
Allow the crackers to cool on a cooling rack and get completely crisp before snacking. Store them in a jar in the pantry for up to a week.