for @midasinc, who asked about food!
It's definitely not a dumb question! Sometimes the small details are the hardest to write and research, but they really add a lot of depth to your setting.
One of my primary motivations for learning French was because I HATE reading British sources on France from this period, which seemingly cannot go more than a few paragraphs without expounding on the superiority of British culture and civilization, and of course, complaining about the French. For example: French people are too happy. French women are too confident and converse with men too easily. French meat is too seasoned.
However, British travel guides are actually great resources for things like this, because they're actually meant to educate readers who aren't already familiar with 19th century Paris. So you can get lots of information about lodgings, culture, entertainment, and yes, food.
So what kinds of foods are we looking at? These are just a few examples of what you might find on Parisian menus in the 1820s-30s:
Meat and poultry: beef, mutton, ham, chicken, goose, duck, turkey, veal, partridge, quail, pigeon
Seafood: salmon, carp, turbot, mackerel, sole, oysters by the dozen
Vegetables: beans, potatoes, spinach, lettuce, asparagus, artichoke, celery, sorrel, cabbage
Fruits: lemon, pear, apple, apricot, cherry, plum, orange, grape, peach, strawberry, raspberry
Sauce: above British writer also complains that the French put sorrel sauce on everything.
And of course, bread, cheese, and wine. For actual meals, please refer to the menus.
One thing that struck me about the high-end fine dining establishments is the sheer size of the menus, which could have upwards of 100-250 dishes! I was originally going to post an actual menu, but that would make this post way too long, so you can just find them in my linked sources. For dinner at one of these restaurants, you might order a bottle or half-bottle of good quality wine, bread, a potage (thick soup), meat and fish, a vegetable entremet, dessert, and a small glass of liqueur. An English writer estimates the average cost of this meal at a fashionable restaurant to be about 9 francs, though one may be able to get a similar meal at other restaurants for 5-7 francs.
These prices, however, should not be considered the average cost of a meal in general, as it is noted that cheaper restaurants serve "four dishes, half-a-bottle of wine, a dessert, and as much bread as the guest chooses to eat, for 30 sous" (less than 2 francs.*) Meals could be bought at nearly any price point, from under 1 franc to over 10. At the low end of this range (though they varied widely), you could find traiteurs, eating houses where you could eat in or order food to be delivered to your house or apartment at a fixed time and price. You could also order cooked meats from a rotisseur, or apparently buy the meat yourself and send it to the rotisseur to have it seasoned and cooked.
An English writer notes of the people who live in Parisian apartments, “Many people living in this way keep no servant at all to themselves; they depend on the porter for taking any message which may come for them when they are not at home; they have their dinner sent by a traiteur at a fixed price by the day, and hire a woman by the week to come and make the beds and sweep the room.” This does sound very much like how Marius lives in the Gorbeau house, and Les Amis probably live similarly. Sometimes traiteurs would be attached to a certain lodging house or hotel, but even without it was sometimes possible to get your meals from wherever you lodged, cooked by the proprietress or her cook, as at the Thénardier inn.
It would of course be remiss to ignore the two locations most prominent in Les Mis—the Café Musain and the Corinthe cabaret. The word "cabaret" had not yet come into its modern usage and is typically translated into English as a public house, or pub. Cafés served coffee, liqueur, breakfast and lunch, with "sandwiches, chops, sausages, eggs, pates, with Burgundy, or some other excellent wine." It is noted that cafés do not usually serve dinner or supper.
Could they cook for themselves? Putting aside the question of should they cook, the answer is...it depends? A writer from the 1860s claims that nearly every apartment had a kitchen, albeit a very small one, basically a tiny room or alcove with a fourneau. But even if you don't have a kitchen, if you have a fire, you can theoretically cook. (And even if you don't, I guess—Marius doesn't have a fire but cooks his own meat, so presumably he uses Mme. Burgon's kitchen?)
Sorry for the long post, but we are talking about food…in France.
* 1 franc = 20 sous, 1 sou = 5 centimes
The New Picture of Paris, from the Latest Observations (includes menu for Grignion's)
A Narrative of Three Years' Residence in France, Principally in the Southern Departments, from the Year 1802 to 1805
Bentley's Miscellany, Volume 54
Tait's Edinburgh Magazine, Volume 1
The Student's Guide to the Hospitals and Medical Instituions of Paris
John Wiblin (M.R.C.S.), 1839
A Rough Sketch of Modern Paris
John Gustavus Lemaistre, 1803
A New Picture of Paris, Or, The Stranger's Guide to the French Metropolis (includes menu for Very's)
Galignani's Picture of Paris, Being a Complete Guide to All the Public Buildings (includes menu for Brizzi's and Les Trois Frères Provençaux)
Edited 1/27/22: a correction, added another source
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