Peel and chop the onions. Trim and slice the celery. Peel and thickly slice the carrots. Halve the squash. Scoop out the seeds. Peel and chop it into large chunks. Drain and rinse the lentils. Dissolve the stock cube in 1 ltr boiling water.
Warm 2 tbsp oil in a large pan. Add the onion and celery. Season. Cook and stir for 5 mins. Add the carrots and squash. Cook for 5 mins, stirring, till the veg are softening. Stir in the stock and lentils. Cover. Bring to the boil. Turn the heat down. Simmer for 15 mins.
Peel and roughly chop the potatoes. After 15 mins cooking, add the potatoes to the pan. Simmer for 10 mins till the potatoes are almost soft. Finely slice the greens, discarding any thick stalks or cores. Add to the pan. Simmer, uncovered, for 5 mins to wilt the greens.
Roughly chop the herbs. Stir into the scouse. Taste and season. Serve in warm bowls.