In a small bowl or measuring jug, dissolve 1 tablespoon of the sugar into 1 cup of lukewarm water. Sprinkle in the yeast and whisk until fully dissolved. Leave to rest in a warm place for five minutes, until the mixture becomes frothy and the yeast are activated.
In a large stand mixer bowl, whisk together both flours, the remaining sugar, and salt until evenly combined.
Create a well in the centre of the flour mix, pour the wet ingredients (the eggs, oil, honey, and the activated yeast mixture) into the well and gently mix with a wooden spoon until a soft, shaggy dough begins to form.
Add the remaining water gradually at your discretion, kneading until the dough becomes soft and elastic, while taking care not to overhydrate it.
Add the remaining water gradually at your discretion, kneading until the dough becomes soft and elastic, while taking care not to overhydrate it.
Transfer the dough to a lightly floured surface and knead gently by hand, folding and pressing until it comes together into a soft dough. Lightly dust the top with flour and continue folding the dough over itself a few times until smooth, supple, and shaped into a neat dough ball.
See 'How to Knead a dough by hand'
Place the dough into a lightly oiled bowl, brushing a little oil over the surface to prevent it from drying out. Cover with a clean cloth and leave to proof in a warm place for 1½–2 hours, or until doubled in size.
Once risen, gently knock back the dough and transfer it onto a lightly floured surface.
Divide the dough into eight equal portions. Lightly knead and shape each piece into a short, thick rope. Cover loosely with a clean cloth and leave to rest for five minutes to allow the dough to relax before shaping.
Roll each piece into an even rope, then braid four ropes together to form each challah loaf, carefully tucking the ends underneath for a neat finish.
Leave the braided challahs to proof for a further 30–45 minutes, or until lightly puffed and airy. Generously brush each loaf with a honey-egg wash, then finish with a scattering of sesame seeds.
Bake in a preheated oven at 200°C / 180°C fan / Gas 6 / 400°F for 25–30 minutes, until deeply golden with a beautifully glossy crust.