In a large bowl,
combine the yeast, water and sugar. Stir, and leave
for 15 minutes to dissolve.
Add the
buttermilk, bicarbonate of soda, salt and butter and
stir to blend. Stir in the whole meal flour. Add just
enough of the plain flour to obtain a rough dough.
Knead on a
floured surface until smooth. Divide into three
equal parts. Roll each into a cylinder, then cut in
four.
Grease a baking
sheet. Form the pieces into torpedo shapes, place on
the baking sheet, cover and leave in a warm place
until doubled in size.
Preheat the oven
to 200C/ 400F /Gas 6. Brush the rolls with the
egg. Bake until firm, about 15-20 minutes. Leave to cool on a wire rack.