This was a fun question. First, a bit of background:

Aztec food largely came from two sources. The first of these was the tribute system, which we know of largely from the Codex Mendoza. I won't discuss it here, as it represents a rather diverse set of agricultural methods specific to each town and the crops they produced for tribute. The second major source for the Aztecs was the Chinampas system, which was a system of raised beds separated by shallow canals in the lakes of the Valley of Mexico. These beds were made of the shoveled mud from the decomposed organic matter at the bottom of the lake and were possibly the most productive agricultural system in the world at the time. This system still exists today, which means we have somewhat modern data for it. Taking numbers from Martínez Ruiz [1] citing an older paper from the '50s, yield at the time was an astonishing 3,000-4,000 kg/ha, translating to 44-60 bu/acre. This is comparable to yields in the US until the 1960s [2].

But wait, there's more. This is yield from the 50s, maybe they were using modern fertilizers and modern variants (despite what the paper says about traditional methods). I dug up a rather infamous paper from De Montellano [3] about Aztec Cannibalism that provides some helpful numbers about precolumbian yield. Because this paper is focused on nutritional yield, it breaks things down into dietary components. Luckily, they've calculated two sample diets for us, one consisting of 400g of daily corn and the other with 300g. These numbers are reasonably in-line with what I'd expect from my own area. Since they give the chinampas area (9000 hectares) and the number of people they support (180k), we just have to pull the math through:

((population * daily_intake * 365) / area) ~= 32-45 bu/acre

Keep in mind that this isn't even the full productivity of the chinampas system, as only 2 of the 7 annual harvests were corn. That's a simply astonishing level of agricultural productivity and highlights how Tenochtitlan became one of the largest cities of the medieval world.

[1] Martínez Ruiz, J. L. (2014). The chinampa: a sustainable high efficient agrohydrologic system for shallow lacustrine and wetland areas. Water Practice and Technology, 9(3), 324-330.

[2] https://www.agry.purdue.edu/ext/corn/news/timeless/YieldTrends.html

[3] De Montellano, B. R. O. (1978). Aztec cannibalism: an ecological necessity?. Science, 200(4342), 611-617.