# How ecash is minted

To use Cashu, a user Alice first needs to acquire ecash tokens. For that, Alice's wallet has to do two things: First, Alice asks the mint for a Lightning invoice and pays it using any other Bitcoin Lightning wallet. Second, when the invoice is paid, Alice generates a secret x and blinds it (i.e. encrypts it) and sends it to the mint. The mint then signs this blinded secret which we call a blind signature C'. The mint then sends the blind signature back to Alice and her wallet unblinds (i.e. decrypts) it to obtain a signature C on the secret x which the mint has both never seen. The tuple (x, C) is an ecash token and can be sent around to other users as a form of untraceable money.

[extracted from the Cashu PoL scheme document]