Preheat oven to 325°F and line 2 baking sheets with parchment paper.
Add cheese, flour, and salt to a food processor. Pulse until a crumbly mix forms. Then add butter and pulse a few more times.
Add milk and then pulse a few more times until you can start to see a dough forming.
Remove the dough from the food processor and place it into a large bowl. Use your hands to form a dough.
Divide the dough in half and roll out one half at a time onto a lightly floured surface or use the parchment paper you have prepared for the pan. You want the dough to be VERY thin.
Use a pizza cutter, pastry wheel, or knife to cut into squares. Then use a fork or skewer to poke a hole/holes into the crackers.
Place crackers on the parchment lined pans and sprinkle with additional salt.
Bake 17-20 minutes or until the bottoms of the crackers become golden brown.
Cool completely on the pan.