Place the flour in a large bowl. Add the yeast on one side of the bowl and add the salt on the other side. Salt should not be placed on top of the yeast, as it can kill it and make in in-active. Stir the ingredients together until evenly mixed.
Add a good splash of olive oil. Measure out 340ml/12fl oz water and add three-quarters to the flour mixture, and mix together by hand, then add the rest of the liquid.
Turn the dough out onto a work surface and knead by hand until the dough looks silky and stretchy. This will take approximately 10 minutes.
Oil a medium sized mixing bowl and place the dough into the bowl. Cover with cling film and set aside to rise, for about an hour, or until the dough doubles in size.
When risen, turn the dough out onto a lightly floured work surface and knead, to knock the dough back. Shape the dough into a ball.
Divide the dough into eight equal pieces then roll out each piece into a strand about 40cm/16in long.
Lay the strands out on the lightly floured surface like an octopus, fanned out from a central point at the top. Stick all the ends at the central point to the table with your thumb.
For the following braiding sequence, number the strands of dough from 1-8 from left to right. Every time you move any strand it will take the new number of its position in the row. Step 1: place 8 under 7 and over 1 Step 2: place 8 over 5 Step 3: place 2 under 3 and over 8 Step 4: place 1 over 4 Step 5: place 7 under 6 and over 1 Repeats step 2-5, until all the dough is braided.
Tuck both ends of the loaf underneath to give a tidy finish.
Place the plaited dough onto a floured baking tray, and leave to prove for another hour, until risen again.
Preheat the oven to 200C/375F/Gas 5.
Brush the loaf with the beaten egg wash and bake in the oven for 20-25mins.