Why not try something as simple as this :
$variables = array();
$variables['name'] = "Robert";
$variables['age'] = "30";
$template = file_get_contents("template.html");
foreach($variables as $key => $value)
{
$template = str_replace('{{ '.$key.' }}', $value, $template);
}
echo $template;
Your template file being something like :
<html>
<p>My name is {{ name }} and I am {{ age }} !</p>
</html>