// before...

_rootFeature = Create
                    .FeatureViewModel
                    .WithChildFeature(Create.FeatureViewModel.WithChildElement().WithChildElement())
                    .WithChildFeature(Create.FeatureViewModel);

///////////////////////////////////////////////////////

// after, refactored w/lambdas & linq ;D

_rootFeature = Create
                .FeatureViewModel
                .With(2)
                .ChildFeatures(c => c.First().With(2).ChildElements());