They open it shortly after Ben's death.
They'd been planning this for a long time... her and Ben, and eventually, Peter, too. It'd been a lifetime dream, but with May working night shifts and Peter too young to work, it had just never been able to quite work properly.
Then Ben died, and Peter found May crying over notebooks full of plans and notes from her business class and he decided no.
"Let's open the cafe," He said, smoothing the hair back from her face and gently leading her to the kitchen. "Ben and May's. We'll have all kinds of sweets and drinks and we'll get that spiffy new coffee machine that you always wanted. We'll use Uncle Ben's life insurance and then you can spend your days in the bakery and I'll man the counter and we can live in a little room behind the shop, just like we always wanted, yeah?"
May stared at the envelope of money on the counter, and Peter's mind flashed to when she shouted, "I'll never use that money!" at the funeral.
He half expected her to scream, to get angry with him for taking advantage of his death like that, but Peter just wanted May to smile again, and he remembered that she had always laughed whenever they brought up the cafe, so this was his last ditch attempt.
(He couldn't lose his aunt too, not so soon.)
To his relief, a small, hesitant smile graced her lips. "Yeah." She agreed softly, curving her fingers over Peter's. "I'd like that."
And suddenly the broken, grieving woman from the past month was gone, replaced by the Aunt May from before, the one that was bold and strong and beautiful.
(A bit sadder and wiser and older but still May, still completely, now, May, instead of the woman who sobbed on the mess and tried so hard to help Peter when she herself was so obviously falling apart.)
They scoured New York for a place to buy, saved up (Peter found a job as a newspaper boy and used all the money for their cafe savings) and eventually, they got there.
Ben and May's opened a few weeks later, and by then they had long since taken care of legalities with a lawyer and May had agreed that while her cooking and baking was fantastic, there were some recipes that would never taste good.
Then, bam, it was a go.
Peter worked the counter and May worked the kitchen.
They lived in a comfy little room in the bed that had a couch and fairy lights and a nice bunk bed with bookshelves and lots of pillows.
It was like a dream, except the wonder didn't really end.
(Except, of course, nights where they were dead tired and didn't want to work but had to and ended up drinking ten gallons of coffee to stay awake. But even that was pretty fine.)