I won't buy shop pesto. It never tastes right, and is never anywhere near as appetising as home-made. I suspect economies in their choice of oil and cheese. Unless you can grow your own basil, awkward in the Cornish climate, you have to buy the potted growing stuff, which isn't too bad if it's glossy and fresh-looking. I don't bother if all I can get is a bunch of limp leaves in a plastic bag. The pine nuts are a bit pricey too. So it isn't the cheapest, but I agree, it has to be home-made, even with a pot of fresh shop basil if that's all you can get. The one thing I think can be overdone if you're not too careful is the garlic...

I bought a huge pot of basil last weekend for a pasta recipe that calls for a basil sauce, which is just basil, a touch of garlic and quite a lot of extra virgin olive oil, all whizzed up. Then I suddenly got ill and didn't do the recipe. I think I'm OK now and the basil still looks good. So it could be Friday night with a good glug of the ould Italian red...