Hmmm.. I've been curious about this one.. do you think it called for too much lemon juice?
Not sure...upon reflection I'm thinking it could also be the sun-dried tomatoes giving it the bitter taste. I had a second bowl without the tomatoes and while I could still taste the lemon, it was better without the tomatoes. So next time, less lemon and no sun-dried toms, one avocado instead of two, and spinach instead of basil...lol...I love spinach pesto! Sadly, I am notorious for messing around with recipes.