Epazote grows wild in lots of places (you can find it all over Chicago and just about every other city that I've lived in).  But you can find it in many of Mexican groceries as well (especially if the owners are from central or southern Mexico--not the north).  If you can't identify it growing in the wild or locate any in Mexican groceries, then my suggestion is that you scatter some seeds somewhere and grow your own.  It likes full sun, not-too-rich soil, not much moisture--in fact, it likes to be kind of stressed as it grows (the most vigorous epazote that comes up in my yard every year comes sprouts between cracks in the sidewalk).  A good source for seeds is johnnyseeds.com or seedsofchange.com.  Epazote does well in pots, too.  Just be warned that when it goes to seed, hundreds of seeds will scatter through your yard.  They will sprout in the spring, whether you live in Texas or North Dakota. 

Sincerely,
Rick

The quince dessert was probably ate de membrillo, and, while it is do-able at home (as your mother proved), it requires a certain knowledge of how to work with the natural pectin (the gelatin-like substance in the quince that sets up the dessert)and of sugar-fruit cooking stages. A little more than I can go into here. I can help you with the enchilada sauce recipe, though: Boil or roast under a broiler 1 1/2 pounds husked tomatillos until they are soft. Blend with 3 garlic cloves, as much chile (serrano or jalapeo) as you like, and a handful of cilantro. Heat 1 1/2 tablespoons oil in a medium-size saucepan over medium-high, then add the tomatillo puree and cook until thick and reduced, stirring nearly constantly. Add 2 cups chicken broth and simmer over medium-low for a few minutes. Season with salt. Add 3 or 4 tablespoons of cream if you'd like.

Sincerely,
Rick

Thanks for the nice note.  I LOVE the Yucatan--rich history, delicious food, great music, beautiful beaches.  I had a great time shooting Season 5 of Mexico: One Plate at a Time in the Yucatan.  But I live in Chicago ... Not exactly the right climate for growing sour oranges.

Sincerely,
Rick

Chihuahua cheese is a melting cheese that originally came from the northern Mexican state of Chihuahua, where Mennonite settlers made it popular around a century ago.  Now it is commercially made all over Mexico, in a style that resembles a good brick or Monterey Jack cheese (that's a little different from the Mennonite version, which is a bit more mild-cheddar like).  In the United States, only one company holds the trademark to make Chihuahua cheese:  the Chicago company V&V Supremo, distributed mostly in the Midwest.  Other companies make comparable cheese and typically call it some variation on "quesadilla cheese" or "asadero cheese."  If you can't find any of those, simply substitute a good-quality brick or Jack cheese.

Sincerely,
Rick