[chef] Iterating over attributes in a template

[Landon < >]

This might be a fundamental misunderstand on my part, but I can't
figure out how to iterate nested attributes in a template.

Here's what I have so far:

Recipe
template "/tmp/config.xml do
  source "config.xml.erb"
  variables :interface => node[:config][:interface]
end

Attributes file:
default[:config] = {
  :interface => {
    :total_cards => "75",
    :relevant_results => "6"
  }
}

Template:
      <% @interface.each do |x| %>
      <% end %>

The error I get:
Chef::Mixin::Template::TemplateError (You tried to set a nested key,
where the parent is not a hash-like object

Thoughts?  I have been beating my head on this.

Thanks,
Landon