Home made soup - the ultimate in frugal food

It has to be, doesn't it?  I don't mean the posh kind where you poach a while salmon in champagne before discarding the fish and using the stock reduced down to a thimbleful . . .
I mean the kind where you boil up a few bits and bobs and end up with a wonderfully warming, tasty, healthy bowlful - several, in fact.

Today I made roasted root veg soup and this is how.  All the veg was leftover from the week or what I always have in anyway.

Ingredients:
2 carrots, peeted and cut into smallish chunks
2 parsnips ditto
2 medium potatoes, ditto
2 or 3 small onions (or one larger one), peeled and sliced roughly
2 garlic cloves, peeled
1 tbsp sunflower oil
a sprinkle of cumin - I suppose it must have been about 1/2 tsp, maybe a little more.  Use your own favourite.
some marigold stock powder.  I use the reduced salt kind.  You could use a meat stock.
Boiling water
a good handful of red lentils - sorry, I didn't weigh them
Salt and pepper to taste

I also had the last few tomatoes that I salvaged from my blighted plants, ripe but the skins are hard and they're not very juicy, so I chopped them in half and used them too, for a bit more flavour.

Method:
Place the chopped veg (including the garlic) in a poly bag, pour over the oil and give the whole thing a good mixing.  This way it stops your hands from getting oily and messy which I hate.  If you dont mind, you can just use your hands to toss the veg in the roasting dish.  When all the veg is coated, tip it into a roasting dish, grate some black pepper over it all and slowly roast at about 160 C.  I left them in for well over an hour, turning them now and again.
When the veg is all soft and roasted with crunchy bits, sprinkly over some Marigold powder - I think it was about 1 good tsp.  Add boiling water and put back in the over for 10 mins or so.  This loosens all the lovely bits from the side and bottom of the dish.
Pour into a saucepan, add the lentils and more water if needed and simmer gently until the lentils are cooked.
Zizz well.  I used my stick blender and then pushed it all through a sieve.  Check seasonings and adjust if wanted.  Heat to piping hot and serve.  I will put a dollop of yogurt in just before I eat.  It was very thick so could make a lot more by diluting with more stock, milk etc.

And why is it frugal - well, partly because of the cheap ingredients, all of which I had in the house but also because out a few vegetables and seasonings I have now got the main part of my lunches for every day next week.  Good, filling portions that will only need a piece of fruit to complete the meal.  That really cannot be bad, can it?