dough: In a medium bowl, combine the yeast, warm water, and 1 teaspoon sugar and give it a little stir. Let it sit for about 5 minutes, until it becomes foamy on top. Meanwhile, in a large bowl or the bowl of stand mixer fitted with a dough hook, mix together the salt, flours, za'atar (if using) and remaining sugar. In a separate medium bowl, whisk together the eggs and oil. When the yeast is foamy, add it to the dry mixture immediately followed by the egg mixture and stir to combine. Knead, either by hand on a floured surface or with a dough hook for 7-10 minutes, adding more white flour as necessary (but try not too add too much), until you have a smooth and slightly sticky dough. Transfer the dough to an oiled bowl, cover it with plastic wrap and let it sit at room temperature until it has doubled in size, about 2-3 hours. to shape: Divide the dough into 4 or 8 parts, depending on how big you'd like your loaves to be. Pat them out into long rectangles (about 2 1/2" x 9" for personal rolls, 2 1/2" x 18" for medium loaves) and then spread with a thin even layer of ricotta. top with a sprinkling of additional cheese, if desired, and a sprinkling of salt. Roll up the rectangles the long way so you have long skinny snakes and and pinch the edges well to seal in the cheese. Roll the snakes into spirals to get round loaves and then let them rise for 30 more minutes. Preheat the oven to 375ºf. Brush the loaves with a thin even layer of egg wash and then sprinkle with pumpkin seeds, sesame seeds, salt, and pepper and bake until golden brown. Begin checking for doneness after 25 minutes. Let cool slightly and enjoy! Preferably with a fresh tomato. Do the challah/fresh tomato double fist.