Tahini is pure sesame seed paste. Think of it as similar to nut butter, only made with sesame seeds. Traditionally, tahini sauce is made with tahini paste, lemon juice, garlic, and salt. Falafel sauce is typically made either with tahini or yogurt and different spices. Our family thinks the tangy, garlicky tahini sauce in this recipe is the best of both worlds. Vegan cream cheese is added to soften tahini's bitterness while adding the cool, creamy quality of yogurt.