Position a rack in the lower third of the oven and heat the oven to 450°F.
Make the topping:
In a small bowl, stir the sesame seeds, poppy seeds, and fennel or caraway seeds. Fill another small bowl with water and set it aside along with a pastry brush and the kosher salt.
Make the dough:
In a large bowl, whisk the all-purpose flour, whole-wheat flour, and table salt. Add the olive oil and 1/2 cup water to the flour; stir with a rubber spatula until it collects into a soft, crumbly ball of dough. Use the spatula or your hands to press the dough against the sides of the bowl to gather all the stray flour.
Set the dough on a lightly floured work surface and portion it into thirds. Pat each portion into a square. Set two squares aside and cover with a clean towel. Roll the remaining dough into a rectangle about 1/16 inch thick and 7 or 8 inches wide by 14 or 15 inches long. Whenever you feel resistance, lift up one edge of the dough and sprinkle more flour underneath before you continue rolling.
With a pastry brush, brush the dough lightly with water and sprinkle about a third of the seed mix evenly over the surface. Sprinkle with 1/4 tsp. of the kosher salt. With a dough scraper, pizza cutter, ravioli cutter, or sharp knife, cut the dough in half lengthwise and then cut across to make rectangles roughly 2 by 4 inches. Don’t bother trimming the edges; rustic edges add character.
Transfer to an unlined baking sheet. Bake until nicely browned, about 10 minutes. Let cool on a wire rack.
While each batch is baking, clean your work surface as needed and repeat the rolling and cutting with the remaining portions of dough. Store the cooled crackers in a zip-top plastic bag. They’ll keep for up to a week.
Rosemary & Sea Salt Crackers: Add 2 Tbs. chopped fresh rosemary to the dry ingredients in the dough. Skip the seed topping and instead sprinkle each batch of crackers with 1/4 tsp. fine sea salt.
nutrition information (per serving):
per cracker, Calories
1, Fat Calories
10, Saturated Fat
1, Monounsaturated Fat
4, Polyunsaturated Fat
Photo: Scott Phillips