This bread is fairly sweet in flavour and goes very well with a more savoury topping, such as salami, cheese, Swedish caviar or a combination of cheese and caviar or cheese and salami.
Heat the water and milk to 37 C, then disolve the yeast in the liquid in a bowl.
Add treacle, salt, white rye flour, half the wheat flour and butter to the bowl.
Start working the dough and gradually add the rest of the flour until you reach a good texture. The dough should be fairly firm, but not hard, and no longer stick to the bowl. Keep working the dough for 10 minutes if using a mixer or twice that time if you kneed by hand.
Cover the bowl leave to rise until double in size.
Turn out the dough onto a surface dusted with flour, divide into two equal parts and form loaves.
Grease two tins of about 1.5 liters with butter and put the loaves in them.
Cover and leave to proof until the loaves spring back when gently prodded, around 30 minutes. Whilst you wait, heat the oven to 200C (400F, gas mark 6).
Bake in the lower part of the oven for 35-40 minutes.
Mix coffee and treacle and brush the loaves as soon as they come out of the oven.
Let rest in the tin for 10 minutes before placing the loaves on a wire rack and letting cool completely.