The easiest way I found to accomplish this is to use the DefaultL2LGroup on the hub ASA. On the spoke ASA you will use a tunnel group equal to the ip of the hub ASA. Post your configs if you need a hand.
Hub ASA
tunnel-group DefaultL2LGroup ipsec-attributes
pre-shared-key *
Spoke ASA
tunnel-group ipsec-attributes
pre-shared-key *
Configure the rest the same way you would any other L2L tunnel.