use strict;
use IO::File;

my $var1='test';
my $var2='test2';

my $f = new IO::File "$var1/$var2/blah.conf","w" or die "Can't create blah";
print $f <<FRED
  blah blah
  ...
FRED
;

##</code><code>##

open HANDLE, ">$HANDLE" or die;
$HANDLE="$var1/$var2/blah.conf";