This is my favourite salad dressing! Well, it's the only one I use, I don't like buying store bought ones anymore, I'd much rather make my own healthier ones from scratch. I make a jar-full each time and it does keep for a while in the fridge (well, it's never lasted more than maybe 2 weeks max with me, I think...I use it a lot, so can't vouch that it keeps any longer than that). :)
1 1/2 cup plain greek yoghurt
3/4 cup olive oil
3 tsp turmeric powder
1 tsp cayenne powder
Add yoghurt and oil, then spices in a glass jar. Mix very well until completely combined. Close jar and store in fridge. You may have to just mix it a little before each use, since the oil tends to separate.
It makes a delicious creamy bright yellow dressing. These spices also have a lot of health benefits, I'll post something about spices some time soon. :)