Blockchain technology is basically a method of recording transactions on a public, distributed ledger. It provides a foolproof, verifiable, and largely immutable record of the transactions.

All the transactions are recorded in a digital "block." Each block of data is mathematically verified through a process called "mining."

When the latest block of transaction records is verified by one of the "miners," that block is added to a chain comprising all previous blocks. Therefore, the "blockchain."

Once a block has been added to the blockchain, it becomes part of a permanent record that is, for all intents and purposes, unalterable.

This great innovation was first applied to Bitcoin. However, it has many possible applications beyond cryptocurrencies, including for smart contracts, financial services and banking, and voting in elections.

(Given that I am hampered by a severe lack of technical knowledge, my answer comes in at far less than 5 minutes. If the interviewer wanted at least 5 minutes, I'd fail the interview. But, as you know, I do not want to work anyway. :-)

(As for your comment about "would not enjoy doing" the job, then I'd say don't pursue it. If one cannot enjoy his/her work, it aint worth doing!!)