In a small bowl, combine 2 tbsp. of warm water, yeast packet, and a pinch of sugar. Whisk together until the yeast is dissolved. Cover with a clean tea towel and let sit for 10 minutes until foamy.
In a large separate bowl, mix flour, the rest of the sugar, and the salt. Make a well in the centre of the flour mixture.
Pour into the centre of the well, the yeast mixture, half of the two beaten eggs, and the oil. Mix together slightly then add the lukewarm water and stir.
Once slightly mixed together, use your hand to combine the rest of the way.
Pour out onto a floured surface and knead for 10 minutes until dough is smooth and springy. When dough starts to get sticky, you can add a bit of flour but try to use as little flour as possible.
When finished kneading your dough, pull the sides of the dough down and try to form a nice ball. Place into a lightly oiled bowl and coat in a thin layer of olive oil. Cover with a clean towel and place in a warm place for 1 hour, or until the dough has doubled in size.
Line your 9”x13” baking dish with parchment paper.
Once risen, remove from the bowl and place dough onto a clean surface. Cut the dough apart into three equal pieces. You can use a scale for exact weight measurements.
Roll each of the three pieces out into long sausage shaped cylinders with tapered ends, approximately 13” long.
Place the three pieces of dough about 1/2” from each other on the worktable. Bring the top of the tapered edges together to connect them. Braid the dough. At the end of the braid, bring the tapered edges together and connect them.
Gently lift off of the table and place into your baking parchment lined dish. Cover with a clean tea towel and let rise for another 40 minutes until braid has risen and is pillowy.
Once risen, preheat oven to 400℉/200℃/Gas Mark 6.
Use the rest of your beaten egg and coat the top of the challah making sure to get into the crevices of the bread. If adding seeds, sprinkle them on top of the challah after coating the challah with the beaten egg.
Place bread into oven on second lowest rack and bake for 25-30 minutes. Check after 15 minutes to make sure that it is not browning too quickly on top. If it is browning too quickly, place tin foil on top of bread and continue to bake the challah. You will know that it has finished baking when the challah sounds hollow when it is tapped on the bottom and the bottom is a golden-brown colour.
Cool on a wire rack then serve.