You can’t. But what you can do is use a Draw Material to Render Target node in blueprints. If you draw to a Render Target asset, you can reference it in your Texture Object node. If you use a Create Render Target node, and draw to that, replace the Texture Object with a Texture Object Parameter node in your master material. Then create a dynamic material instance of your master material, and use a Set Texture Parameter Value to reference the Render Target being drawn to.