From the book missing from the NYPL:
CALIFORNIA
MEXICAN-SPANISH
COOK BOOK
Selected
Mexican and Spanish
Recipes
By
Bertha Haffner-Ginger
1914
Pg. 45 (photo):
TACO
Made by putting chopped cooked beef and chile sauce in tortilla made of meal and flour; folded, edges sealed together with egg; fried in deep fat, chile sauce served on it.