C# Convert hierarchical model to other model

Question

I have a hierarchical data ApiGroup as shown with below properties. This get populated from Api, I want to map this model into UIGroup model with below properties. Please suggest a efficient approach to do the same?

• ApiGroup: List<ApiItem> Items

• ApiItem: string Text, List<ApiItem> SubItems

To be converted into model

• UIGroup: List<UIItem> Items

• UIItem: string Text, List<UIItem> SubItems

Note:- here first retrieving hierarchical Items from Api and then map them to UI model to show on screen.