DB<110> %hash = ("fred" => "flintstone", "dino" => undef, "barney" =
+> "rubble", "betty" => "rubble");

  DB<111> use Data::Dumper

  DB<112> print Dumper \%hash
$VAR1 = {
          'barney' => 'rubble',
          'betty' => 'rubble',
          'dino' => undef,
          'fred' => 'flintstone'
        };
[download]

and if you really need to avoid an explicit loop, then %hash in list context will give you keys and values correctly paired.

  DB<115> $length = 0 + keys %hash
 => 4

  DB<116> printf "%10s\t=>%10s\n" x $length, %hash;
    barney    =>    rubble
     betty    =>    rubble
      dino    =>          
      fred    =>flintstone
[download]

though for readability I'd rather prefer

  DB<123> $template = "%10s\t=>%10s\n" x (0 + keys %hash)
%10s    =>%10s
%10s    =>%10s
%10s    =>%10s
%10s    =>%10s

  DB<124> printf $template, %hash;
    barney    =>    rubble
     betty    =>    rubble
      dino    =>          
      fred    =>flintstone
[download]