In a small bowl, dissolve the sugar in warm water, sprinkle in the yeast, and set it aside until it bubbles. Combine the flour and salt in a large mixing bowl, make a well in the center, and pour in the yeast mixture and olive oil. Stir vigorously in one direction, until the ingredients are well-blended and the dough pulls away from the sides of the bowl.

Turn the dough out onto a lightly floured work surface and knead for at least 10 minutes, adding more flour a tablespoon at a time, until the dough is smooth. Clean out the bowl, oil it lightly, then put the ball of dough into the bowl and cover it with plastic wrap or a damp dish towel. Set in a warm spot to rise until the dough is twice its original size, from 1-2 hours.

Preheat the oven to 450°F and position two racks in the center. Since lavash is thin, the racks can be close together.

Knead the dough briefly and divide it into 12-16 pieces. Sprinkle the work surface and a rolling pin with flour, then roll each piece into a thin 8x3" square. Peel the dough off the surface and transfer it to a lightly floured baking sheet. Prick holes in the dough with a fork, brush or spray it lightly with water, then sprinkle with sesame or poppy seeds, or a combination of the two. Three pieces of dough should fit comfortably on a large baking sheet. Once the first sheet is full, put it in the oven to bake for 3-5 minutes, until it is golden brown; continue to roll and bake until all are finished. Let the breads cool completely before serving with soup, cheese or spreads.