If your cash on hand is from sales, then the implication is you recorded a transaction in QuickBooks to record those sales. Usually this is done using Invoice/Payment combination or a Sales Receipt.
When you record Sales Receipts and Payments for cash, and then use the cash, the best way to handle this is to "deposit" the cash into an account that's not really a bank account, but is set up in QuickBooks as a bank account. This is similar to how Petty Cash is usually tracked.
After creating the deposit, then in QB you have less in your "Undeposited Funds" account available to deposit into your real bank account.
After spending the cash, create a transaction in that account to reduce the balance, much like writing a check or withdrawing money from your real bank account.
