Gather your ingredients so that you have everything close at hand on the counter or table.
Prepare the Cracker Dough
Cream together the sourdough and softened butter in a large mixing bowl with a paddle attachment.
In a small bowl, combine all-purpose flour, Vermont Cheddar Cheese Powder, and kosher salt.
Add the flour to the creamed mixture. Mix together just until combined and a soft dough forms, about 30-40 seconds.
On a lightly floured surface, knead the dough 4-5 times. Form into a ball, then flatten with your hand. Cover with plastic wrap and refrigerate for at least 2 hours or overnight.
Form the Crackers
When ready to make the crackers, remove the cracker dough from the refrigerator. Preheat oven to 350 degrees.
Divide dough into 2 parts. Place a sheet of parchment paper on a flat working space and lightly sprinkle it with flour. Position the dough in the center and using a rolling pin, begin rolling out the dough from the center to the edges. Sprinkle the dough with more flour if needed. Roll the dough out as thin as possible. Strive for at least 1/8" thick, but thinner is even better.When you think your cracker dough is thin enough, roll some more to make them even thinner! Another option would be to use a pasta maker.
Transfer the dough and parchment paper to a baking sheet. At this time, I like to roll the dough even more using a small pastry/pizza roller.
Using a fork or roller docker, poke holes in the dough.
Brush melted butter over the cracker dough.
Cut the dough into squares or other desired shapes with a pastry wheel.
Sprinkle the crackers with sea salt. Repeat with the second ball of dough onto a second baking sheet.
Bake the Crackers
Bake both sheets on middle racks in a preheated oven for 6-8 minutes. Rotate pans from top to bottom and from back to front to help the crackers bake more evenly. Continue baking for another 6-8 minutes. Watch to make sure the edges don't burn.
Remove from oven and transfer parchment paper to cooling racks. Cool completely before serving.
Store crackers in a covered container at room temperature. This recipe will make 40-50 square crackers.
Notes
*Unless otherwise indicated, all butter used on this recipe site is salted.