Mix 1 cup all purpose flour, 1 cup whole wheat flour, 1 teaspoon salt, and 2 tablespoon light olive oil in a large bowl.
Add warm water, little by little, and knead to make a soft dough. The amount of water will depend upon the quality of the flour.
Transfer the dough to a work surface and knead for 6-8 minutes until smooth and soft.
Oil a big bowl and transfer the dough to the bowl. Cover and keep aside for 90 minutes at room temperature.
Preheat the oven to 360 degrees F (180 degrees C). Transfer the dough to the work surface. Divide it into 4 equal parts.
Lightly dust the surface and roll the dough into a very thin rectangle (⅛ inch). If the dough is not thin the crackers will not come out crispy. You can also use a pasta maker to roll your dough. Keep the remaining covered with a cloth to avoid drying.
Lightly brush the crackers with water and sprinkle white and black sesame seeds on top. Roll the rolling pin over the seeds so that they get embedded in the dough. Cut into triangles using a pizza cutter or a sharp knife. Transfer the triangles on a large baking sheet in a single layer.
Keep the tray in the middle rack of the oven and bake for 10-12 minutes, until lightly browned from top. Remove from oven. Cool for 10-12 minutes. Store in an airtight container.
You can use multigrain flour to make these crackers. Keep a close eye while baking the crackers. They burn in the blink of eye.