if you need or want to change the price displayed – for example adding “from” to a price , or changing 0.00 to “free” or however else you’d like to display a particular price of a particular item you could use the following filter(s) in your theme’s functions.php.

add_filter('wppizza_filter_loop_meta','myprefix_loop_price_filter', 10 ,2);
function myprefix_loop_price_filter($meta, $post_id){
/**
change post_id as appropriate for the menu item 
where you would like to change the output
**/
if($post_id==49 ){
add_filter('wppizza_filter_output_format_price','myprefix_item_price');
}else{
/* reinstate default */
remove_filter('wppizza_filter_output_format_price', 'myprefix_item_price');
}
return 	$meta;
}
/** output the price as required */
function myprefix_item_price($price){
static $i=0;/* prices/sizes are zero indexed */
/* 
$i==0 to only affect first price/size, $i==1 to only affect second price /size, and so on. omit if($i==xx) to change all prices 
*/
if($i==0){
$price=__('from').' '.$price;/**change "from" / "price" as appropriate**/
}
$i++;
return $price;	
}