Well I'm not sure if this is what you are asking, but here is the idea.

.....
foreach my $row  (0..($rows-1)){
    foreach my $col (0..($cols-1)){
        #$arrayVar->{"$row,$col"} = "$row,$col"; 
        $arrayVar->{"$row,$col"} = "    ";
    }
}
.....
....
.....

$arrayVar->{"1,1"} = 42;

Tk::MainLoop;
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