Recently, my Pinterest account has been plagued with vegan brownies that replace butter with puréed avocado, black beans (yes, black beans) or sweet potato. “The best brownies,” the captions read. “You can’t even taste the vegetables!” But in many cases, you can (at least in my experience), and they just don’t taste like brownies. This recipe is the exception. Made with chia seeds, dates, and walnuts, you’ll end up with rich, chocolatey, chewy delights.