Making crunchy creamy hash browns
The way I have achieved this is by gently simmering the potato cubes until they soften. (You want them pretty much cooked, but not so done that they won't hold together well.) 

I also lightly salt the water so they take on a little seasoning while they cook. This, of course, is optional.

Next, I drain the potatoes very well. I want them to essentially be dry for the next step. Lastly, I lightly coat the surface of a non-stick pan with oil and cook the cubes on a medium heat, tossing as needed, until they are browned to my liking. 

This results in potatoes that are crunchy on the outside and still creamy on the inside.