Cut potato, squash and shallots in half-length ways, brush cut sides with oil.
Put vegetables, cut sides down in a shallow roasting tin. Add garlic cloves. Roast in preheated oven at 190c/375f/gas mark 5 for 40 minutes or till tender and light brown.
When cooked ad cooled, scoop the flesh from the sweet potato and squash and put in pan saucepan with insides of the shallots. Remove the garlic peel and add the soft insides to the rest of the vegetables.
Add stock and a pinch of salt. Bring just to boil, reduce heat and simmer, partially cover for about 30 minutes stirring occasionally, until the vegetables are very tender.
Allow soup to cool the blend and puree until smooth.
Return soup to sauce pan and stir in milk. Season to taste then simmer for 5-10 minutes until completely heated through. Eat with a spoon full of cream swirled for effect.
For Vegetarian omit the Chicken Stock. For Vegan omit cows milk and single cream also.