Here is today’s menu from what is arguably the best restaurant in Mexico City or the world. I had cactus soup, green salad with vinaigrette, carrots and chayote, green enchiladas with chicken, cream and black beans, lemon gelatin, guava juice, and a baguette.
This including the tip I gave cost me just under $7 US, which is not the least expensive lunch you can have in Mexico but I repeat, it is the best. Note that 85 pesos the menu and 10 the tip, would take a minimum wage worker 1.5 days of work to earn.
There are sit down lunches to be had for 40 but it is very easy to see why people are looking for stands where you can get 5 tacos for 15.
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It is my eighth day in Mexico and so far I have spent on average $35 every day not including most lodging, although this has included some traveling ($20 in cabs, $40 in bus tickets, $35 one hotel that I had not paid for already) and minor shopping (a DVD for $8, a ring for $20).
Now that I am not eating breakfast out, or using cabs or intercity buses, can I bring this down to $20? Perhaps and perhaps not: consider movies, theatre, books. In any case I just took out 6,000 pesos which, using my figure of 14 is $430, and we will see how long it lasts.
Axé.
coldhearted scientist وداد 
Nice. And I understand every word of the menu due to my deep understanding of Mexican food!
I love seeing photos of your travels.
Glad you’re enjoying it; greetings from the Colonia Roma branch of the bookstore Péndulo. Do you see why I say it is not exploitative to travel to, and enjoy poorer countries than one’s own?
Update: $430 lasts 12 days. I charged a couple of things (hair dye and cut, a pair of jeans, a couple of books) but they were not essential. One way or another I am spending, then, $36 a day plus my rent which is $22, that makes $58; let’s be super safe and call it $75 for next year, which includes weekend travel; that is $2250 in a month which means the real budget for a month in Mexico with flight is $3000, minus what one saves by not being at home (many of the expenses I have here, I would have there … gas, food, books, movies, weekends, clothes, hair); which means that by teaching the summer class I am basically funding this month. It means, also, that with what I make next summer I can finance at least one more month, arguably 2 since the flight will be covered and since some of what I spend, will be what I would spend at home. Result: it is a break-even thing, and other ways of fixing the house and paying debts must be found. I will live on rice and beans I think.
Also, I note: I really and truly do not spend a lot on food here. Key to not spending a lot here generally is not to ever start spending a lot on food. I, the budget goddess, have spoken.