How to Create AO + Lighting Renders?

NURBS

I've seen these amazing renders all over the internet showing an untextured model with just lighting and some ambient occlusion but I cannot find any tutorials that show how to make them.

How exactly do I make a render look like this?

WillDettrey

NURBS, You should be able to follow this tutorial to get similar results: https://marmoset.co/posts/lighting-interior-scenes-with-exterior-lighting-in-toolbag/