Not gonna lie, lottery. If that seems shallow, consider a few things...
Many of my dream jobs involve money simply to get there. For example extensive training or a Masters degree so that I have the right level of education and experience. If I won the lottery I could be a millionaire AND be closer to achieving my dream job.
Many of my dream jobs are also based on how much money I would earn. For example, working with animals, or books, or children, would all be lovely jobs, except I have to work out how I would earn money doing those things. If I wont the lottery I could have my REAL dream job, even a ****ty paid job, because I wouldn't have the worry of what salary I'd be getting.
In short, I would win the lottery, be a millionaire, move somewhere lovely, and probably translate novels freelance with absolutely no worry over how much work I get or how well it pays because I have no financial worries and it is fun.
Alas :'( :'(