In a bowl, sprinkle the yeast into about one third of the water. Leave for 5 minutes; stir to dissolve. In a large bowl Mix the flour and salt together . Make a well in the center and pour in the yeast water.
Pour the remaining water into the center of the well. Mix in the flour from the sides of the well. Stir in the reserved water, as needed, to form a firm, moist dough.
Turn the dough out onto a lightly floured work surface. Knead until smooth, shiny, and elastic, about 10 minutes.
Put the dough in a clean bowl and cover with a tea towel. Leave to rise until doubled in size, about 1 ½ - 2 hours. Knock back, then leave to rest for 10 minutes.
Shape the dough into a long loaf about 35 cm in length. Place the shaped loaf on a floured baking sheet and cover with a tea towel. Prove until doubled in size, about 30-45 minutes. Turn the oven to 425°F/220°C
Cut five diagonal slashes, each about ¼ in (5mm) deep, across the top of the loaf. Bake in the preheated oven for 25-30 minutes until golden brown and hollow-surrounding when tapped underneath. Leave the baked bread to cool on a wire rack.
Notes
In the summer or a warm kitchen the bread will rise more quickly.