In a food processor, combine the shredded sharp yellow cheddar, all-purpose flour, cornstarch, and salt. Pulse for about 30 seconds until well blended.

Add the cold butter, cutting it into the dry mixture until the texture resembles wet sand, around 20 seconds.

Drizzle in ice-cold water while pulsing until large clumps form—about 10 pulses. Do not overmix.

Transfer the dough onto a floured surface, shape into squares, wrap in plastic wrap, and refrigerate for 45 minutes.

Preheat your oven to 350°F (177°C). Line baking sheets with parchment paper.

Roll out each square of dough to about 9 inches wide. Trim to 8-inch squares and cut into 64 small squares, poking holes in the centers.

Sprinkle with sea salt and bake for 16 to 20 minutes, rotating halfway until lightly golden.

Let the crackers cool completely on the baking sheets to enhance crispiness before serving.