Just create CPT and Taxonomies and paste this code into you archive.php, it will display different dropdowns with each taxonomy you have.
<?php
if (is_post_type_archive() || is_tax()) :
$post_type_obj = get_queried_object();
//if is tax, we'll have to append taxonomies cause they doesnt exist on "taxonomy object".
if(is_tax()){
$taxs = get_taxonomy($post_type_obj->taxonomy);
$taxs = $taxs->object_type;
$taxs = get_taxonomies(array('object_type'=>$taxs),'names');
$post_type_obj->taxonomies = $taxs;
}
if(empty($post_type_obj->taxonomies)){
return;
}
echo '<form id="recipesFilters" method="get" action="">';
echo '<label>FILTER BY</label>';
foreach ( $post_type_obj->taxonomies as $tax_name ) {
$tax = get_taxonomy($tax_name);
echo '<select name="'.$tax->query_var.'">';
$type = get_terms( array($tax->query_var), array('hide_empty'=>true) );
echo '<option value="">'.$tax->labels->name.'</option>';
foreach ($type as $t){
echo '<option value="'.$t->slug.'">'.$t->name.'</option>';
}
echo '</select>';
}
echo '<input type="submit" value="Search" />';
echo '</form>';
endif;
?>

