I have white satin ice. I have several wilton gel colors and some Ameri-color gels......

What two colors will successfully make brown fondant? Would the same principals apply as with paint?

I usually add a little of black with the brown color to get a deeper brown. Depending on the brown shade I will also add red, orange or yellow.
Whenever I have to dye something brown, black or red that's when I curse not buying the color pre-made and then wasting a lot of my americolor.