In a large bowl, sprinkle the yeast over the water. Let stand for about 5 minutes to dissolve the yeast.
Stir in the salt, sugar, oil and 4 eggs until well blended.
Gradually mix in the flour. When the dough becomes too stiff to stir, turn it out onto a floured surface and knead for 8 to 10 minutes. Place dough underneath the bowl to rise until double in size. Or, you can place the dough in the bowl, and cover with a towel.
Punch down the dough, and divide into 6 or 8 even pieces depending on what shape you want. Remember to take a small piece of the dough off and make a blessing, according to Jewish law.
Roll the pieces into ropes. Plait into two loaves, or one really big 6 piece plait - but only if your oven is large enough.
Tuck the ends under and place on a baking sheet to rise until your finger leaves a small dent when you gently poke the bread.
Preheat the oven to 200 degrees C. Whisk together the remaining egg, water and vanilla sugar or essence. Brush the glaze over the tops of the loaves. Sprinkle sesame seeds over the top.
Bake in preheated oven for 35 to 40 minutes, or until the bread is deep golden brown. Wrap the small piece of dough that was blessed in aluminum foil, and burn in the oven as an offering while the other loaves are baking.