Preheat oven to 350° F.
Combine all ingredients, and blend well in a high speed blender. I like to use a blender cup for minimal cleanup. If you haven't soaked your cashews but you're otherwise ready to go, you can boil them for five minutes first, but know it will be slightly grainy. A small sieve can help. Set aside, this is ready to go.
Heat a 10-12 inch skillet on medium low heat. Add oil, saute onions until they begin to brown. Add garlic, vegan crab, and jalapeño to taste. It's of course fine to leave it out entirely if you prefer low-heat, or sub another, spicier pepper if you prefer lots of heat. You can always garnish with more if you're serving a crowd and aren't sure. Remove filling from pan and place in bowl to the side.
Add another tablespoon or two of oil if needed to the pan, and warm tortillas one at a time on each side to make them pliable.
Set tortilla to the side, and add another to the pan. While it is warming, fill with one heaping tablespoon of filling, and roll. Place in casserole dish. Repeat.
Cover with two-thirds of the Creamy Jalapeño Sauce, setting some aside for garnish. Bake uncovered at 350° F until it begins to brown and appears set.
Remove from oven, place onto plates, garnish, and serve!
*Lactic acid adds my favorite cheesy tang, but if you don't have any, 1 tbsp apple cider vinegar, lemon juice, or even juice from sauerkraut will work as well. If you're using pickled jalapeños, try the juice even!