Cut the carrots, onions and baby marrow into small cubes. Set the baby marrow cubes to one side.
Heat the oil in a large pot and add the onions and carrots. Fry for a couple of minutes, then add the chopped garlic. Cook for a further minute, without allow the garlic to brown.
Add the water and the contents of the KNORR Vegetable Stock Pot, along with the tinned tomatoes, origanum and thyme.
Bring to a boil and cover. Simmer for 10 - 15 minutes, stirring occasionally.
Add the reserved baby marrow cubes, the drained lentils and the spinach (or Swiss chard), and simmer for a further 8 minutes.
Season to taste with salt and pepper and add a squeeze of lemon juice for freshness.
Serve hot with grated Parmesan cheese and wholewheat bread.