Mix yeast in warm water. Let sit 5 minutes. In a large bowl combine salt, sugar, eggs and oil. Add yeast mixture. Slowly add flour, stirring until not too sticky. When the dough becomes too thick to stir, turn it out onto a floured board and knead, adding flour as necessary. Scrape the working surface with a plastic dough spatula from time to time, to keep a dry skin from forming on it. You may find that you need more flour, but don't add too much more, or the dough will become heavy. Knead until the dough is smooth and elastic (about 10 minutes).
Form dough into a ball and place in a lightly oiled large bowl, turning to coat the dough with oil. A ceramic bowl is best. Cover the bowl with a clean cloth and leave in a warm, draft-free place to rise for 1 1/2 hours, or until doubled in bulk. After the dough has risen, punch it down and divide it into 6 balls. Let the dough balls sit for 5 minutes, covered.
Keeping dough balls covered while working, remove a ball and roll it between your hands (or on working surface) into a cord about 1 inch wide by about 20 inches long. The dough is quite elastic, making it nicely workable, yet also tending to make it shrink back slightly after being lengthened. I find it best to lengthen it in a series of passes. Form 3 cords this way, and then start from the middle and braid them into a single loaf. Tuck the ends under. It's a little harder to figure out how to start braiding from the middle, but the loaves come out more even and attractive that way. Don't pull the cords while braiding. Place the loaf on a lightly oiled baking sheet, and cover it with a cloth while you form the other loaf. Keep the loaves well apart on the baking sheet, since they will expand a lot. Cover the loaves and place again into a warm, draft-free place to rise for 45-60 minutes.
After the loaves have risen, gently brush the tops with beaten egg using a soft brush, and then sprinkle with the seeds. Bake at 350 degrees F. for 30 minutes, or until golden brown.
Continued in Part 2