The docs from CGI::Cookie indicate that it already supports automatic serilization of simple datasturctures:

... The value can be a scalar, an array reference, or a hash reference. (At some point in the future cookies will support one of the Perl object serialization protocols for full generality).

use CGI::Cookie;

$cookie2 = new CGI::Cookie(-name=>'preferences',
                           -value=>{ font => Helvetica,
                                         size => 12 } 

print header(-cookie=>[$cookie2]);
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