"Overview of Operators" Cheese Material Question

[jpriceoc]

I'm currently learning Houdini and have been doing the course Houdini 9 Introduction. The lessons are doing a mousetrap, mouse, cheese etc.. on the "Overview of Operators" lesson, its calling for a new material to put on the cheese .. a stucco. I don't have that in my Material Palette. Did I do something wrong?

How do you add a new material?