Yep they invented it.
Not really steamed though I guess, vertically broiled.
" LOUIS' LORE
One day in the year 1900 a man dashed into a small New Haven luncheonette and asked for a quick meal that he could eat on the run. Louis Lassen, the establishment's owner, hurriedly sandwiched a broiled beef patty between two slices of bread and sent the customer on his way, so the story goes, with America's first hamburger.
The tiny eatery that made such a big impact on the eating habits of an entire nation was, of course, Louis' Lunch. Today, Louis' grandson, Ken, carries on the family tradition: hamburgers that have changed little from their historic prototype are still the specialty of the house. Each one is made from beef ground fresh each day, broiled vertically in the original cast iron grill and served between two slices of toast. Cheese, tomato and onion are the only acceptable garnish -- no true connoisseur would consider corrupting the classic taste with mustard or ketchup.
More than just another eating place, Louis' Lunch has held a special place in the hearts of New Haveners for generations. When it was threatened with demolition some years ago to make room for a new high rise, scores of people from all walks of life took up the cause for its preservation. Plans for its relocation were finalized just hours before the deadline and in a thirty minute journey by truck, the pocket-size landmark was moved to its present spot on Crown Street.
To help in the reconstruction, friends and supporters sent thousands of bricks from every corner of the globe. Each one has its own unique story and Ken Lassen proudly points them out to special visitors as he takes them on a "tour of the walls".
It doesn't take long for a lunchtime crowd to fill Louis' as it has every working day for more than three quarters of a century. Since most of the handful of seats are quickly taken, most of the customers just hurry in the door, yell out an order "to go" and hurry out again, taking with them a little bite of history. "