Combine the water, yeast and sugar in the workbowl of a stand mixer, stir well and let stand for 5-10 minutes or until good and foamy.
Meanwhile, combine the flours, salt, and lard in a bowl and work in the fat with your hands until broken up into very small pieces.
When the yeast is foamy, fit the mixer with a dough hook attachment and gradually add the flour on low speed until its all incorporated. Scrape the sides down between additions. When the dough comes together, turn it onto a floured work surface and knead until smooth and elastic, 5-10 minutes, adding more flour if necessary. Alternatively, you can let the machine do the work.
Coat a large bowl with the Olive Oil, then put the dough in, turning once to coat both sides. Cover loosely with a clean dry towel, or plastic wrap. Let the dough rise in a warm place until doubled in bulk, about 1-1/2 hours.
Punch the dough down and shape into a flat round about 9 inches across (it will expand to about 10″.) Place the dough on a lightly oiled baking sheet. Sprinkle the top with sesame seeds, about 2-3 Tbsp should do it, then press them lightly into the dough. Loosely cover the loaf and let rise until doubled in bulk, about 1 hour.
When the dough has risen, remove the cover, gently brush with the egg wash then gently place into a preheated 425 degree F oven for 10 minutes. Turn the heat down to 375 degrees F for an additional 25 minutes or until it’s golden brown and sounds hollow when tapped.