Preheat oven to 300 degrees F. Line baking sheet with parchment paper.
Combine all ingredients and stir until a large ball of dough forms.
Spread dough evenly onto parchment-lined baking sheet, about 1/8" thick.
Score the dough to form squares.
Bake for 30 minutes, rotate baking sheet, and bake an additional 15-30 minutes. Baking time depends on the thickness of your crackers.
Crackers are done when they are crisp. Let cool and then break into squares.
Notes
If you're using whole flax seeds, grind them in a high speed blender or coffee grinder before combining with other ingredients. These crackers store well in an airtight container for up to 2 weeks.