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Our poster luckyfatima will disagree, but I prefer tahini from sesame seeds that are Roasted. Otherwise the product tastes bland and way too much must be used for flavor balance, IMO.
In hummus and baba ghanoush I like both the nutty tahini And lemon tastes to be more noticeable than any garlic; therefore I'm not a fan of most commercial products.
The canned varieties like Joyva have worked better for me. Organic tahinis usually seem be bland and/or unroasted. Al Wadi and IndoEuropean brands are common but at the bottom of my list. Whole Foods Market usually has a good selection.