Dynamic Template File

My environment file has a config section with name, value pairs in it. I am trying to output a template of those name, value pairs by putting the below code into my erb file in chef:
<% @config.each do |setting| -%>
<%= setting[0] %>=<%= setting[1] %>
<%end-%>

This works great the first time as it creates a property file with my name value pairs.

The problem is when the config section changes. I get a Permission denied error, but if I rerun the recipe then everything works and the new value is in the property file.

How can I create dynamic property files from the environment json file?

Thanks,
Will