Calabacitas Gratinadas con Quesillo

This is a Oaxacan dish. Specifically from the Valles Centrales, where calabacitas, sweet corn, and chile de agua all come from the same morning at the Mercado de la Merced in the city of Oaxaca, and where every cazuela on the table at midday holds some version of this gratin.

The chile de agua is what makes this dish Oaxacan and not generic. It is a fresh chile, pale green, mildly hot, with a thin skin and a clean grassy flavor that grows almost nowhere outside Oaxaca. Roasted on a comal, peeled, and torn into rajas, it gives the gratin a smoky thread that no poblano and certainly no bell pepper can replicate. If your chile vendor does not know what chile de agua is, you are not at an Oaxacan mercado. Find one, or accept that you are making a different dish.

The quesillo is the other half of the equation. Not mozzarella. Not string cheese. Quesillo de Reyes Etla, made in the small town outside the city where the cheese has been pulled by hand for generations. It melts into long soft layers, salty and milky, and it is what the senoras of the valley reach for when they want a vegetable dish that feels like an occasion.

My mother did not cook Oaxacan food. She was from Jalisco. But I learned this gratin from a senora named Doña Catalina who had a comedor on the road between Oaxaca and Etla and who fed me a version of this every time I came through with my recorder. She would not let me leave without writing down the proportion of crema to milk in my notebook. Cada estado, su propia cocina, and this one is hers.