When bad debts are recognized, the debtors account is closed by Posting PnL as a loss on the credit side of the debtor (in this case W.Blanco)
Accepting that, W. Blanco's account no longer exists in your books of accounts.
However, later on, when you have recovered the money lost, it comes in as a way of cash / bank, in this example it is Cash.
Hence the journal entry: Cash Dr.
Bad Debts Rec A/C : Cr.
At the end of the year, the Bad Debts Rec account balance will transfer into the profit and loss account as an income, just the way discount received does.