1. Preparation of required materials: a copy of valid identification (such as ID card or passport), a statement of loss of chef's certificate (relevant forms need to be filled in) and relevant application fees (please consult relevant local authorities for specific fees) are required.

2. Report the case and obtain the report certificate: you need to report the loss of the chef's certificate to the local public security bureau or police station and obtain the report certificate. The report form is one of the important documents to reissue the chef's certificate.

3. Contact Shanghai Catering Association: As the issuing authority of the chef's certificate, you need to contact Shanghai Catering Association to find out the specific process and requirements for reissue. Will guide the submission of required materials and pay related fees.

4. Submit application materials: According to the requirements of Shanghai Catering Association, the above prepared materials need to be submitted. This includes the application form, report certificate, copy of identity certificate, etc. Ensure that the materials provided are complete and meet the requirements.

5. Payment: According to the regulations of Shanghai Catering Association, you need to pay the corresponding replacement fee. Please inquire about the specific information of payment method and amount.

6. Waiting for approval and obtaining a new certificate: all materials have been submitted and the fees have been paid, and it is necessary to wait for the completion of the approval process. After approval, you can go to Shanghai Catering Association to get a new chef's certificate.