Mix the yeast and 750 ml flour in a mixing bowl.
Add all the remaining ingredients except the extra flour and beat well.
Add just enough of the extra flour gradually to form a dough which can be handled comfortably.
Take care not to make the dough too firm for it will be difficult to work with and the end result will not be ideal.
Turn out the dough on a floured surface and knead for about 5 minutes until smooth and elastic.
Sprinkle the dough lightly with flour, return to the bowl and cover and allow to rise until doubled (about 30 minutes).
Turn out the risen dough onto a floured surface and flatten with the palms of the hands.
Sprinkle the olives and cheese over the dough, enclose into the dough and knead gently to distribute evenly.
Grease a baking tray with butter.
Divide the risen dough into 2 - 3 portions and shape into elongated loaves.
Place the loaves onto the baking tray and brush with egg and water mixture.
Slash the tops diagonally with a sharp knife or kitchen scissors and allow to rise uncovered in a very mildly warm spot until doubled.
Preheat the oven to 180°C while the breads are rising.
Bake for about 30 minutes until golden brown and thoroughly cooked if tested with a metal skewer and sounds hollow when tapped with the knuckles.
Cool on a wire rack and store airtight and refrigerated.