Hi

We use a/p and bank rec

What is the best way to void a cheque?

The best way is to Reverse (not Void) the check in BankRec. It is the best for two reasons - one is that Reversing will restore the paid invoices and generate the reversing GL transactions, and two is that BankRec can send the pending status changes to AP and thus save work.

Note that reconciliation status changes need to be posted in both BR and AP for completeness.