If you want to mine a block -- no matter the transactions in it -- you'll have to mine at the same difficulty as EVERYONE ELSE.
If anyone could mine a block easily then bitcoin's security model would be broken.
Put differently, there's only 1 block roughly every 10 minutes world wide. You can't just mine for your own convenience. You can't just make transactions and "stick them in a block and mine it."
Your transaction has to be placed in one of these global blocks. And there's only one block every 10 minutes. And all the miners in the world are competing for it. And there's a lot of miners.