I've not found mulatos in SD. Northgate doesn't carry them either. A lot of the commerical produce companies do carry a wider selection of dried chiles than retail grocery stores do. Try Specialty Produce since they sell to the public as well as the trade. If not, you may need to order on-line or make a trip to L.A.
MexGrocer sometimes has them. They're headquartered in La Jolla tho' I doubt their warehouse and shipping facility are located there.
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Technically, a mulato is a dried poblano. It is a poblano that has been allowed to more fully ripen before the drying process begins. Anchos are also dried poblanos, but are dried when green, mulatos are allowed to go beyond the green stage (to yellow and red) before they are allowed to start drying.
The flavor profile is more complex than an ancho. As with any fruit or vegetable that's been allowed to actually ripen (as opposed to being picked or used before fully ripe) the flavor is richer and deeper. Mulatos have a deep, rich,slightly smoky, somewhat chocolatey flavor with traces of licorice (hmm....sounds like I'm describing a wine doesn't it). Some people include the mulato in the holy chile trinity...ancho, pasilla and mulato, others include the guajillo instead of the mulato. Mulatos (along with chihuacles) can be a key ingredient in some moles because of the complex flavor it imparts.
The most common substitute for mulatos is an ancho.
You can probably find mulatos at the Mercado Hidalgo in Tijuana
No, a chile negro and chile mulato are not the same thing.
A chile negro is actually another name for the chile pasilla. A pasilla is a dried chile chilaca.
Are you confused yet :-). The problems arise from the fact that dried chiles are frequently mislabled in the U.S. even in Mexican grocery stores, and then compounded by the fact that the chiles may go by multiple names in Mexico depending upon the region. That said, here's a quick down and dirty chile identification note
Ancho chile = dried green poblano.
The chile has broad shoulders (stem end) about 2 - 4" across and tapers to a rounded point. Skin is wrinkled When you open an ancho chile and hold it up to the light, the chile will be a nice deep burgundy color.
Pasilla chile = dried chilaca chile.
The pasilla is a much narrower chile. It is generally no more than about 2 inches wide and taper to a point abd is about 4" in length. Skin is wrinkled. When you cut open a pasilla and hold it up to the light the chile will be a tabacco brown color.
Chile mulato = dried, fully ripe poblano
The mulato will have the same general appearance as the ancho but should be a darker color. Most of the mulatos I've seen and used have tended to be somewhat smaller than an ancho. I don't know if that is a function of allowing the chile to fully mature or not.
California Chile = dried anaheim chile
About the same size as a pasilla except the skin is much smoother.
If subbing for the mulatos, I would probably use anchos. Or another option would be to order a package of chile chihuacle from Melissa Guerra - http://www.melissaguerra.com/food/chiles-spices - in San Antonio, TX. The chihuacle has the flavor profile you're looking for, especially for mole, and Melissa Guerra is one of the few sources for it in the U.S. The link has pretty decent photos of chiles.
This link - http://www.foodsubs.com/Chiledry.html - has pretty good definitions and pictures of various chiles, common and not. If you look at the photo of the ancho, mulato and pasilla you can see the differences. Compare the mulato in the photo to the chile negro offered by MexGrocer and you'll see they're not the same. Compare the pasilla in the photo to the chile negro and you'll see they look very similar.
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