If using dried yeast, dissolve the sugar in 500 ml (18 fl oz) of lukewarm water, then sprinkle in the dried yeast and set aside for 15 minutes, or until it is frothy. If using easy-blend yeast, add it directly to the flour.
Sift both flours and the salt into a large mixing bowl. Pour the yeast mixture, or 500 ml (18 fl oz) of lukewarm water if using easy-blend yeast, into the centre. Stir to form a dough, adding a little extra warm water if it is too dry, then knead until the dough forms a ball and leaves the side of the bowl clean.
Turn out the dough onto a lightly floured surface and knead for 5 minutes, or until it is smooth and elastic.
Grease a bowl with oil. Roll the dough around in the bowl so that it is lightly coated with oil and loosely cover the bowl with cling film. Leave the dough to rise in a warm place for 2 hours, or until doubled in size.
Turn out the dough onto a lightly floured surface, punch it down and knead for 1-2 minutes. Divide the dough in half.
Roughly flatten one half. Sprinkle the olives over it, fold the dough over and knead until they are evenly distributed. Cut the dough into ten equal pieces and form them into round or torpedo-shaped rolls. Lightly dust each roll with a little wholemeal flour, then arrange them, at least 2.5 cm (1 in) apart, on a baking sheet and score slashes in the top of each roll.
Repeat Step 6 with the remaining dough, using the sunflower seeds instead of the olives.
Loosely cover all the rolls with cling film and leave to rise in a warm place for 30 minutes.
Meanwhile, heat the oven to 230°C (450°F, gas mark 8). Bake the rolls for 20-25 minutes until they are golden brown and sound hollow when tapped on the bottom. Serve them warm or at room temperature.
Tip: both the baked rolls and the dough freeze well. Freeze the dough after the first rising, before it is shaped into rolls. Defrost for 8 hours in the refrigerator, or for 2-3 hours at room temperature, then proceed from Step 5.
Nutrition is given per olive roll. Each sunflower seed roll has an additional 9 calories and 1 g fat.