I've grown Defender and Romanesco and Son #2 is growing Picollo, which are round almost like baby marrows.
It was the courgette and marrow glut a few years ago, that prompted me to try making chutney, and I loved the process so much that I've made it ever since. Courgette chutney remains my favourite too.
To make courgette chutney you need:
2lb courgettes, cut up into small chunks
12oz chopped onion
1lb demerera sugar
juice of 1 lemon
1 tbs ground corriander
1/2 tsp cumin
1/2 tsp cayenne pepper
2 tsp mustard seeds
a sprinkle of dried crushed chillies
1 tsp salt
500ml white wine vinegar
Put everything into a heavy based saucepan.
Bring gently to the boil.
Simmer for 2 hours or so, until it starts to thicken up, stirring occasionally.
Pour into warm, sterile jars and seal.
Label when cool.
Leave for a couple of months to mature before eating.
Lovely with bread and cheese.
I'm afraid I can't remember the original source of this recipe... however I have tweaked it a bit!