Lentejas Estofado con Verduras

Earlier this morning I found a vegetable stewpack getting very distressed in the bottom of my Shopping Trolley. It contains Carrot, Celery, a little piece of a leek and a few Nabos (Spanish White Turnip) and should have been put away, in the chill, when I bought it a few days ago. It is now part 'n' parcel of a Lentil Stew, which, while I'm waiting for to cook I will describe.............

Lentil & Veg Stew (Makes quite a lot)
Olive Oil
1 decent knob unsalted Butter
500g Green/Brown Lentils
3 biggish onions
3 Carrots
1 whole celery stick
3 cloves garlic
3 smallish Nabos (or Potatoes)
1 Chicken Stock Cube
1 teaspoon Ground Cumin
1 teaspoon Hot (Spanish Smoked) Paprika
1 teaspoon Ground Black Pepper
5 heaped teaspoons concentrated Tomato puree (bought in small tins here) See notes.
2 tablespoons Red Wine Vinegar
Salt (optional)

PREP
Soak the Lentils for 10 minutes or so.
Dice, fine, mince or crush the garlic (I used minced out of a jar 'cos I had some)
Dice, small, the (peeled) Onion, carrot and (de-stringed) celery
Peel then dice, large, the Nabos/Potatoes
Dissolve the stock cube in some hot water

METHOD
In a large frypan heat a glug of Olive Oil with a knob of butter then throw in the Onion, Carrot and Celery and fry until going golden then reduce the heat a little and add the Garlic, Cumin, Paprika and Pepper and, while turning everything over, fry for a minute or so more. Empty the Frypan into a huge casserole pot. Deglaze the frypan with the stock and add that liquor to the pot along with the drained soaked Lentils, Nabos/Potatoes, Tomato Puree, the Vinegar and more water to cover. Put a lid on the pot and stew at a gentle simmer until all is nicely tender, checking every now and then the water level and topping up if necessary. Check for seasoning then serve in a deep plate with a Wine Vinegar condiment and some crusty bread.

NOTES
My Lentils actually sprouted whilst being cooked!!!
I've a sneaky feeling that the tubed tomato concentrate might be stronger than the tinned that I have used here. So, if using that, go carefully so as not to overpower the dish with tomato flavour.
Snapping the celery into pieces will allow you to de-string it. Try it!