325g (12oz) celeriac
15ml (1 tbsp) lemon juice
25g (1oz) butter
1 potato, peeled and chopped
1 small onion, peeled and chopped
600ml (1 pint) vegetable stock
75g (3oz) Stilton cheese, crumbled
75ml (2½fl oz) double cream
2 rashers bacon, crisp fried, to garnish