Pixian Douban (郫县豆瓣酱) is also essential for this dish. Pixian Douban is a fermented chili bean paste that is characteristic to and ubiquitous in Sichuan cuisine. It's what gives the distinctive appearance of Mapo Tofu with its red oil floating on top. If you can't find Pixian Douban (郫县豆瓣), other brands of spicy Doubanjiang should suffice.