If the $10 coupon is issued by Kroger (KR), the sale is recorded as $90. In addition, debit card transactions are considered cash transactions. Thus, the sale with a $10 Kroger discount coupon would be recorded by Kroger as follows:

Cash ........................... 90
Sales .......................... 90
If the $10 coupon is issued by General Mills (GIS), Kroger would submit the coupon to General Mills for a $10 reimbursement. Thus, Kroger would have an accounts receivable from General Mills, and Kroger would record the sale as $100, as follows:
Cash ............................................. 90
Accounts Receivable ................. 10
Sales ............................................ 100