use Data::Dumper;

use strict;
use warnings;

my $HoA = {
            flintstones        => [ "fred", "barney" ],
            jetsons            => [ "george", "jane"],
      };
my $AoH;
for my $flintstone (@{$HoA->{"flintstones"}}) {
	for my $jetson (@{$HoA->{"jetsons"}}) {
		push @$AoH, {"flintstones" => $ flintstone, "jetsons" => $jetson};
	}
}

print Dumper($AoH);