This is from Matthew Fort in the Guardian (after he had been on hols and everything in his garden had gone mad)...if you google "marrow recipes" or "marrow soup" it will start you off - there are quite a few!
Stuffed supersized courgettes
What is the difference between a supersized courgette and a marrow? I haven't a clue. By the time I got to my sweet Genovese and handsome, ridged Romanesco, they would have been contenders in the mega-marrow section of any horticultural show. Usually people have nothing but snooty contempt for marrow, but I have always had a soft spot for them. The cooked versions will never seduce the eye, but that soft, fibrous, squidgy flesh, soaked in yellow butter, spruced up with salt and pepper has its own subtle delights. This recipe, however, tries to do a little more than that.
1 supersized courgette (or marrow)
1 medium onion
1 stick celery
Olive oil
500g minced lamb
1 tbsp red-wine vinegar
2 tsp harissa
Salt and pepper
Bring a large pot of unsalted water to the boil. Cut the supersized courgette (or marrow) in half down the middle, and each side in half again but across this time, so you have four quarters that are curved on one side and flat on the other. Pop these into the water for five to eight minutes until they are part cooked. Cool, then scoop out all the seeded flesh, so there is a decent-sized trench running the length of each courgette quarter. Finely dice the onion and celery. Heat a couple of tablespoons of olive oil in a pan, add the onion and celery and fry until soft. Add the lamb and fry over a highish heat until cooked through, about 10 minutes. Add the vinegar and boil for a minute. Turn off the heat and stir in the harissa.
Place the courgettes on a nonstick or greased baking tray. Spoon the lamb mince into the trenches down the courgettes and over them if there is too much. Preheat oven to 160C/325F/gas mark 3 and reheat the courgettes for 10 minutes. This recipe freezes pretty well, too.