Preheat the oven to 375°F(190C°). Line baking sheet with parchment paper or silicone baking mat. Set aside.
Mix flour, sugar and salt in a medium-large bowl. Add in the olive oil and water and mix very well with a spatula until you have a soft, just a little bit sticky dough. The dough will seem sticky but you will roll it out very easily. Cover the bowl with a cling film and let the dough rest for 15 minutes at room temperature.
Divide the dough in half. Place the dough onto a lightly floured parchment paper. Sprinkle some flour over the dough. Flour the rolling pin. Roll out the dough approximately 12,5*10 inches (32*26cm) long, 1/16 inches (2mm) thick.
Cover the dough with sesame seeds and press with a rolling pin and go through the dough from the beginning to the end. Repeat this step (going through the dough with a rolling pin) one more time.
Cut out the dough into 2 inch (5cm) squares with a pizza cutter or a sharp knife. Gently transfer the parchment paper into the baking sheet. Prick the dough with a fork to prevent puffing.
Bake for 12 minutes or until the edges become golden brown. Check the oven after 5 minutes. If the dough is puffing, use your fork to prick small holes again. When you turn off the oven, let them stay there for 5-6 minutes or until the top of the crackers turns golden brown. Remove the baking sheet from the oven and let them cool on the baking sheet for 10-15 minutes or until crunchy. Watch the crackers carefully as the color tells when to turn off the oven and take them out. Do the same steps for the other dough.