For the guajillo sauce, place the dried chiles in a large bowl. Fill the bowl with boiling hot water to cover the chiles by about an inch. Set aside for 20 minutes to rehydrate. Drain and place in a high-powered blender.
Meanwhile, heat the avocado oil in a small pot over medium-high heat. Once the oil is hot, add the ½ chopped white onion and 4 cloves garlic, and pan roast until the outer layers begin to char a bit, stirring every so often, about 6 to 7 minutes. Remove from the pot and place in the high-powered blender with the remaining sauce ingredients. Pulse until smooth. Taste and adjust seasonings as necessary. Place the sauce back into the small pot that you roasted the onions and garlic in and simmer over low heat, uncovered, stirring every so often (*see recipe notes).
For the pambazos, place the potatoes in a 4-quart pot of salted cold water and bring to a boil over high heat and cook until just fork tender, about 10 minutes. Drain and set aside.
Heat 1 tablespoon of avocado oil in a large skillet over medium heat. Once the oil is hot, add the minced onion, jalapeño and garlic, and sauté until the onion is translucent, about 5 minutes. Add in the soy chorizo and cook, stirring often, until just heated through, about 3 to 4 more minutes. Add the potatoes and 1/3 cup of the guajillo sauce, and continue to cook, stirring often, until the potatoes are very tender, about 5 to 6 more minutes. Season with the salt and pepper, mix to combine, and set aside. Wipe the skillet with a paper towel (you will use this skillet for to fry your bread).
Remove the guajillo sauce from the heat and place in a large shallow bowl. Using your fingers, gently scoop out and discard the bottom half of the inside of the rolls, leaving about ½” shell. Depending on how large your skillet is, you’ll probably have to work in batches. Using tongs, gently dunk the bread into the guajillo sauce and fry in about 2 teaspoons of oil over medium high heat until crispy, about 2 to 3 minutes per side. Repeat until all the bread is dipped and fried (*see recipe notes).
To build the pambazos, place about 1 cup of the potato-chorizo mixture in the hollowed-out portion of the rolls. Top with about ½ cup lettuce, a couple slices of tomatoes, a generous portion of vegan queso fresco, some chopped cilantro and a couple teaspoons of salsa verde. Place on the top bun and enjoy!