Create a bill. You can call the vendor ADJUSTMENTS.
Debit the account Non Deductable HST on Meals account (which is a subaccount of meals)
Enter the HST 13% on Purchases, or the applicable tax rate
In the HST box at the bottom, manually change the HST by adding a negative amount
This will zero out the invoice/bill.
If you pull an HST report you will see that the ITC’s will be reduced.