Wash and prepare the courgettes and/or the spinach.
In a low, wide pan (see 'Practicalities, Hints and Cheats') heat the oil and butter. If you're doing the vegan version, just the oil.
Add the chopped onion and cook on a low heat until it is soft.
Now add the grated tomato and increase the heat for a minute, just so a sauce starts to form. Add a few tablespoons of water and reduce the heat.
Add the spinach and the courgettes and courgette tops, if you have them. Bring to a steady simmer and then pop the lid on the pan. Simmer for about 10 minutes.
Once the leaves and courgettes have started to cook, add the milk and the chopped parsley and dill. Reduce the heat and cook for a further 10-15 minutes on a low heat, making sure that the mix doesn't start to catch on the bottom of the pan. Gentle but regular stirring !! A little water may be required.
Once everything is tender and cooked, remove from the heat. Sprinkle with some crumbled feta (optional) and serve.