Wowzer! That is a lot of chiles in that recipe PaulJoseph! I would try not to use that much fresh Bird-eyes because they can pretty spicy, they may rot being fresh (but that much vinegar may preserve them). Maybe try another pepper, like jalapeno, or if you can cayenne pepper powder.

That sounds interesting, if a bit scary. Since it is someone you can contact, please ask them to clarifiy if the chiles are to be fresh, dried or smoked. If fresh, go ahead and do the substitution. I would err on the light side as those are round and yours are pointy and they may not measure the same.

I am in Calif, and have not seen this chile, so it is not common, but doesn't mean we can't get it.

Nutcake This is the recipe send by one of my friend from California

Chili Sauce

2 cups chiltepins

8 to 10 cloves garlic

1 teaspoon salt

1 teaspoon oregano

1 teaspoon coriander seed

1 cup water

1 cup cider vinegar

Combine all ingredients in ablender and puree on high speed for about 4 minutes.

Refrigerate for 24 hours to allow the flavors to blend. Because it is so hot, this will last for years in the refrigerator .

That must be a pretty specilized recipe because those chiles are only wild harvested from what I understand.I know the bird eye's but not these. For fresh, I would vote yes. Both are very hot chiles. Chiles can vary in flavor and fruitiness but these are hot chiles, how many are in the dish anyway, is subbing one hot chile for another going to ruin a dish? No.

The main thing I would be concerned about is what form the Chile Tepin is understood to be in. When I did a quick look around the internet, it seems to be used mostly in dried or smoked form and that can make a larger difference to your dish. Does the recipe have any indication? Because this is a wild chile local to only a few areas in North America, I think it likely the recipe is looking for a dried one.

I wonder again what you are trying to make and the source for the recipe?