How do I do this with mysqli (passing field-value array to insert query)

Question

I used to do this with PEAR MDb2:

$fields_values = array(
        'first_name'        => $first_name,
        'last_name'     => $last_name,
        'email'         => $email,
        'p....
    );

$mdb2->loadModule('Extended');

$result_insert = $mdb2->extended->autoExecute('user', $fields_values, MDB2_AUTOQUERY_INSERT);
$new_user_id = $mdb2->extended->getAfterID();

Whats the cleanest simplest way of doing that with mysqli?