Tahini is a paste made from sesame seeds used to make hummus, among other things. It is similar in texture and consistency to natural peanut butter (so make sure to give it a good stir before using). It is usually pretty easily found in most grocery stores (or when I lived in a very small town, I found it on amazon). I haven’t subbed peanut butter or any other type of ground nut spread for the tahini so I’m not sure how it would affect the taste/consistency of the hummus.
Full article: https://www.melskitchencafe.com/zucchini-hummus-2/