Mexico City is the one place on earth where "Mexican food" isn't a category. It's a hundred different regional traditions, each one distinct enough to spend a week studying. Right now, the best address in that ecosystem is Doña Vero in Roma Sur.
1. Doña Vero (Eje Vial 2 poniente, Monterrey 313, Roma Sur)
At Doña Vero, the kitchen pulls from Oaxaca with no apologies. Order the tlayudas and chapulines cream. The grasshoppers cut through any hesitation you might feel about eating insects within the first bite. The wild boar meat, when available, is the real reason to come back. Wash everything down with pulque; the mezcal bar trend is all over the city this spring, but here the house drink is older and more local. Meals run MX$100–200. The place stays open until midnight on Fridays.
2. Casa Licha Pozole (Sur 69-A 513, Justo Sierra, Iztapalapa)
The only real weakness at Casa Licha is also its identity: the place exists on Saturday and Sunday only. Sunday 9am to 7pm, Saturday 9am to 9pm, nothing in between. But the people who show up for the chalupas and chilate know exactly what they're doing. The Guerrero-style cooking here is the kind you don't encounter often north of Iztapalapa. The mixiote and cacao-based preparations take real regional knowledge to produce, and the review count (over 3,000) reflects that. Casa Licha beats El Regreso on cuisine depth and regional distinctiveness. El Regreso wins on being open when you need it.
3. El Regreso (Yosemite 54-B, Nápoles, Benito Juárez)
The most democratic restaurant on this list. El Regreso in Nápoles is open every day until 7:30pm, runs under MX$100 a head, and still puts out chile en nogada and red mole enchiladas that belong in any honest conversation about this city's cooking. The Pollo al Cilantro is the sleeper on the menu, barely talked about and hard to leave alone. The consommé alone justifies a trip to Benito Juárez on a Wednesday.
4. Portón Maya (Calz. Sta. Cruz 78, Portales Norte, Benito Juárez)
Yucatecan food is its own Mexico, and Portón Maya in Portales Norte is where you go for panuchos and habanero sauce with no dilution. The cochinita pibil is the signature. The suckling pig earns its own attention. Prices stay in the MX$100–200 range. The limitation here is real: doors close at 6pm every day of the week. Get there before 5pm if you're serious about eating properly.
5. Taquería Parrilla Leonesa Centro (Calle de Bolívar 29-A, Centro Histórico)
There is something specific about eating tacos al pastor at a parrilla on Bolívar while a mariachi sets up two tables over. Parrilla Leonesa is in the Centro Histórico, open from 8am to 10pm on weekdays. The arrachera is the move here. The live music transforms what would otherwise be a standard parrilla meal into an event. The score runs marginally lower than the top four, and if you're starting from scratch with no plans, Doña Vero is the better choice. But if you're already in the historic center, this is the place to stop.
If you try one place from this list, go to Doña Vero. The tlayudas and chapulines cream will recalibrate what you think Mexican food in this city can be.
