step 1
Combine the yeast, a pinch of the sugar and a couple tablespoons of lukewarm water in a small bowl
Stir to dissolve the yeast, then leave for 10 mins until foamy
step 2
Meanwhile, combine the flour, the remaining sugar and 2 tsp fine salt in a large bowl
Make a well in the centre, then add half the beaten egg, the yeast mixture and the oil
Pour in 200ml lukewarm water (it should feel slightly warm to the touch) and stir with a spoon, then mix using one hand, keeping the other clean while you bring the dough together
If there are a lot of very dry bits, gradually add a little water to just bring it together – you don't want it to get too wet and sticky
The dough should be moist, but not soggy
step 3
Once the dough has come together, turn it out onto a lightly floured surface
Knead using both hands for 10 mins until smooth and a bit springy
If it gets very sticky, add a very small amount of flour – as little as possible
A dough scraper is useful if the dough is sticking to the work surface
Stretch the sides of the dough down and pull together to form a ball
Lightly oil a bowl, then lightly roll the dough ball around the bowl so it's coated in the oil
Cover with a clean tea towel and leave in a warm place for 1 hr, or until dough has doubled in size
step 4
Line a baking sheet with baking parchment
Turn the dough out onto a clean work surface and divide into three equal pieces, weighing for accuracy, if you like
Roll each piece into a long sausage shape about 25cm long, tapering them slightly at both ends
Lay the pieces out in front of you, parallel to one another with a couple centimetres between each
Bring the sausages together at the top end, then plait them down the length, tucking in the ends when you reach the bottom
Carefully transfer the loaf to the prepared baking sheet and loosely cover with a clean tea towel
Leave to rise until puffy and billowy, about 40 mins
step 5
Meanwhile, heat the oven to 200C/180C fan/gas 6
Gently brush the rest of the beaten egg all over the challah, getting it into all the crevices, and sprinkle with the poppy or sesame seeds, if using
Bake on a middle shelf of the oven for 25-30 mins, until the loaf is golden brown underneath and sounds hollow when tapped
Check after about 15 mins – if the top of the loaf has started to get too dark, cover it with foil