How do you make brown food colouring?

Mix a secondary color with a primary color that doesn't make it. A secondary color is a color that is made of two of the three primary colors (red, yellow, blue). The secondary colors are purple, green, and orange. How to make brown "Mix a secondary color with a primary color that doesn't make it" (Example: Green and red make brown). red+blue=purple yellow+blue=green yellow+red=orange red+green=brown orange+blue=brown purple+yellow=brown