Start this recipe by cutting the top off the garlic, drizzle with oil and wrap in foil. Bake in the oven for 25-30 minutes. Also, cook the potatoes in salted boiling water.  Meanwhile, fry the sausages in a dry pan to brown all over. Remove from the pan, discard any fat in the pan and add in the oil, butter, thyme or rosemary and the onion. Saute for 4-5 minutes to soften then stir in the flour and cook for 1 minute. Pour in the cider and evaporate the alcohol, followed by the stock pot, 2 tsp mustard, salt and pepper and a drop of water. Place the sausages back into the pan and bring to the boil. Reduce the heat and cook down for another 4-5 minutes. When the potatoes are cooked, blitz to a mash with salt, pepper, butter and cream. Remove the garlic for the foil and squeeze the garlic puree into the mash and mix well. Serve the bangers and mash into deep bowls.