I've been on the search for a SW friendly way to make a white sauce. I tried a cottage cheese version with not much success. I then came across a yoghurt version so thought I'd give it a whirl. It totally gets the thumbs up from me. Best syn free 'white sauce' I've come across for sure.
Tomato & thyme cod. Just made this - delicious! I added quite a few whole pitted black olives. Served with steamed baby new potatoes dressed with garlic butter, and some salad leaves and red onion in a balsamic and olive oil dressing.