Add the following code to your themes functions.php file or if you know how to create a plugin add it to a plugin.
Modify the html as needed.
function pop_widget_add_time_to_post( $title, $post ){
$time = date_i18n( get_option( 'date_format' ), strtotime( $post->post_date ) );
return $title . '' . $time . ' ' ;
}
add_filter( 'pop_recent_title', 'pop_widget_add_time_to_post', 50, 2 );