Step 1

Preheat the oven to 275 degrees Fahrenheit. Line a 13x18 rimmed baking sheet with parchment paper and set aside. Stir the seeds, cornstarch and salt together in a large bowl. Add the oil and boiling water. Stir to combine. Let the mixture sit for 10 minutes.

Step 2

Spread the batter into a thin layer on top of the parchment paper (a small offset spatula really helps this along). Sprinkle the top with sea salt.

Step 3

Transfer to the oven and bake for about 90 minutes or until golden brown and crisp, rotating the sheet pan as necessary to encourage even browning. Once it is cool enough to handle, move the parchment paper with the cracker on top to a wire rack to cool completely. To serve, break the crispbread into pieces for a rustic look or cut into squares using a serrated knife.