How to add transparent image over white background of the gameobject

Hello, I’m trying to create kind of button (UI is not an option). It should be simple white square with image on it.
There is a way I do this:

  1. Get Cube, set its Z to 0.1
  2. Set size of materials for mesh renderer to 2.
  3. Add material with white background.
  4. Add actual transparent image.
  5. Pick UI/Default shader for transparent image.

Well it works, but I’m pretty sure this is not the right way of doing things. What should I do to make it correct?

Your method is right. But there is other method.

You can write one shader that make this behavior.

I don’t know how to do different. For me it’s easier to have one shader but your method is right.