The reason there are so many complaints about the sauce flavor is because low fat or fat free yogurt is just so wrong. Use real yogurt people! Look at the difference in calories between reduced fat yogurt and the good stuff. Not a big difference. And look at all the ingredients you can't pronounce in the low fat yogurt. You don't want that in your bod. For this recipe I use plain goat yogurt and it's awesome. Any plain whole yogurt would be good! You might be tempted to try with Greek yogurt, but don't! (It's too thick to make nice creamy sauce.)
I use whatever veggies I have on hand like sugar snap peas and broccoli rabe. I added some shallots to the sauce too. So so good!