MVC 5 ViewModel not working as it was in MVC 4

There is a web.config file located in the Views directory. In it the namespaces that should be available for the views are listed. Did you add a namespace to the views web.config in your mvc4 proj that you are now missing in the mvc5 proj?

The listing in the views web.config is a kind of global using statements that applies to all views.

Your view doesn't know where Ingredient or Recipe come from, you need to add a reference to the namespace which those types are under, add @using XXX.Models to the top of your view

@model XXX.ViewModels.NavigationViewModel
@using XXX.Models
...
@foreach (Ingredient ingredient in Model.Ingredients)
{
    ...
}

---

On a side-note you appear to have a half-baked view model implementation. In your NavigationViewModel you are referencing, which appear to be, domain models. It's generally recommended that anything exposed via a view model, is in actual fact, a view model itself. So in your case, I would introduce a couple of new view models to represent an Ingredient / Recipe i.e.

public class IngredientViewModel
{
    ...
}

public class RecipeViewModel
{
    ...
}

public class NavigationViewModel
{
    public IEnumerable<IngredientViewModel> Ingredients { get; set; }
    public IEnumerable<RecipeViewModel> Recipes { get; set; }
}

These would be be created under the XXX.ViewModels which would mean your view would look like

@using XXX.ViewModels
@model NavigationViewModel

...