if a person from America back in 1840 traveled to modern day US for a week via Time Machine, what type of foods would you serve them and what activities or modern inventions would show them? Im sure they were use to a much more "bland diet" than what a person eats now The Amish probably already eat old style foods like back in 1840
I would recommend the person to travel back and bring some of the unpolluted food he/she/div. is used to.
I would make them a chicken curry or a boeuf Bourguignon (but made with a Bordeaux not a Bourguignon wine) & for dessert, an apple & blackberry crumble. Just typical 2020 fare. I would then show them the internet so they could have a good laugh when they discover how we think they lived in their time & if I felt they were up for it I might let them surf internet porn for a while.
invite them to a traditional Thanksgiving dinner to show them how thankful modern day people are for living in America stop by the strip clubs , shop in modern supermarkets to show them how easy it is to get food take them on a non stop flight from San Francisco or NYC and travel by jet from SFO to LaGuardia NYC , they will get the thrill of their lives and enjoy inflight meals.
I'm not sure what I'd give them to eat, but given that as a whole we're generally bigger and healthier than our forebears, I can only imagine them saying, a la Yoda to Luke in The Empire Strikes Back, "How do you get so big eating food of this kind?"
a large pot of beef stew & chicken noodle soup with bread and crackers , and fresh butter, and tea , biscuits , coffee, sugar. and a barrel of salt pork & potatoes with some apple cobbler for desert
If the fellow from 1840 waited just a couple of years or so, he would be familiar with Necco Wafers. They've been making them since the 1840s.
I think a time traveler from that period would be more interested in the variety and convenience rather than the actual food. Plus, it would depend on that person. A city dweller would have access to finer foods and nice restaurants (Antoine's in the French Quarter opened in 1840 as an example). So to show them supermarkets (as somebody else above mentioned), the variety of takeout we have, and the general accessibility to that food that they never had would likely leave them in awe. Then I'd take them to Skyline for a 4-way.
A Chicago style hot dog, which wouldn't make its first appearance for 50 years at the Chicago Columbian Exposition of 1893!