I whisked in the juice of one fresh lemon.
These marinated for about 30 minutes, so the sauce can be made, next.
...add some pepper...
You need about 1/2 cup of walnut oil. This oil is a bit pricey (I found mine at Whole Foods). You could use olive oil, though. I think it would be a good substitute.
While the processor is running, slowly add the walnut oil until you have a thick sauce-- almost like mayonnaise.
Add a handful of chopped fresh parsley, and there you go! Set the sauce aside...
I decided to warm about one cup of tomato jam.
Heat some oil in a pan, and pan fry the chicken on each side to sear.
NOTE: I forgot to wipe off the excess yogurt. Had I done so, I would have gotten a nicer sear. Ah, well.
VERDICT: The sauce is excellent. It has a lot of garlic, and I actually cut back on the recommended about in the original recipe. So, be forewarned. (I've stored the remaining sauce in an air-tight container.) I think the sauce would be excellent on fish. I also think it would be delicious on pasta, too. I like marinating chicken in yogurt, as I think it tenderizes the meat. The lemon flavor was a bit strong, I thought, so I think I'd add half the amount of lemon juice-- I even think lime juice would be a nice substitute. I loved the different textures in each bite-- the creamy polenta, tender chicken and then the chunky bite of tomato jam. Wow! My husband raved about this dinner, and yes, I would make this again. It's super fast, and if you love garlic, you will love this recipe. It's actually quite healthy. (Well, maybe the polenta is a stretch, if there's mascarpone or heavy cream in it!)
Here's a printable recipe.