INSTRUCTIONS

1. Position racks in top and bottom thirds of oven. Preheat to 350°F. Line two large baking sheets with parchment. Set aside.
2. Combine flours with baking powder and salt in a medium bowl. Add oats and seeds, stirring to fully combine. Make a slight well in the center of dry ingredients, then pour in water and oil. Stir mixture with a fork until a sticky dough forms. Cover bowl with plastic wrap and let stand for 30 minutes.
3. Cut dough in half and shape each into a disc. Working with one piece at a time, roll the dough between 2 large pieces of parchment paper to ⅛-inch thickness and approximately 9 x 12 inches in size. Peel off the top piece of parchment and trim edges, if desired. Cut dough lengthwise in half, then crosswise into sixths to make twelve rectangles. Transfer to prepared baking sheet, at least ½-inch apart. Repeat with remaining dough.
4. Bake in top and bottom thirds of oven, switching sheets halfway through, until crackers are crisp and lightly golden, about 20 to 25 minutes. Transfer to a rack and let cool completely, about 30 minutes.