$args = array(
'post_type' => 'my_custom_post_type',
'meta_query' => array(
array(
'key' => 'name_of_field_with_featured_as_value',
'value' => 'featured',
'compare' => '=',
),
),
);
$query = new WP_Query($args);
if($query->have_posts()) :
//usual loop code but with $query as above, note that post related functions are called as usual, e.g. simply the_title(), not $query->the_title()
endif;