Others have explained how to store an array in a hash. It might also be worth mentioning that your code is equivalent to:

my $slice = {
    kind    => $kind,
    prop    => $prop,
    item    => 5, 6, 7, 8, 9, 10, 11
};
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Which is also equivalent to:

my $slice = {
    kind    => $kind,
    prop    => $prop,
    item    => 5,
    6       => 7,
    8       => 9,
    10      => 11
};
[download]