Cakes, Custard and Category Theory: Easy recipes for understanding complex maths by Eugenia Cheng

'Whatever you think maths is... let go of it now. This is going to be different': and true to her word, Cheng's book on mathematics and category theory ('the mathematics of mathematics') starts with gluten-free chocolate brownies. Using the analogy of cooking methods and ingredients, she sets out to explain how mathematicians think, rather than what they think about.