Eggs. I bought the expensive ones once just for laughs and they taste great without the weird funk. Now I have my own chickens, and the eggs are better than anything in the store. It’s probably more expensive though!

Carrots and celery I always buy organic because they seem to take on the flavor of whatever they were watered with. It makes a difference there for me.

And tortillas, I get the local boutique ones instead of the national mass market ones. Big difference there.