Can OnGUI GUI functions render to a RenderTexture?

The easiest way for me to create a HUD for the Oculus would be if I could simply have my OnGUI calls render to a RenderTexture and then put that on a plane in front of the cameras… such a feature could also be used for making a Dead Space-like 3D interface. Can it be done? I guessed I could do it with

void OnGUI()
{ = renderTexture;

but my RenderTexture remains black for me.

No, you can’t do that.