Add the oil to a large casserole dish, fry the onion and garlic over a medium heat for about 5 mins until starting to brown.  Add the spices, stir well and cook for another minute.   Add the rest of the ingredients up to the black beans, cover and gently simmer for 15 - 20 mins until the squash is cooked.   Add the blackbeans and cook for a further 5 mins.   Season to taste.

Serve with rice, baked spuds or wedges and a selection of toppings.    Topping ideas could include guacamole or chopped avocado, salsa, shredded spring onions, grated cheese, sour cream, chopped coriander, sliced radishes, pickled chilli, sliced olives, feta etc etc.