Before prepping meat, mix marinade ingredients. Mix all marinade ingredients except vegetable/canola oil. Set aside.
Start slicing pork roast. Be sure to use a serrated knife so you can get it pretty thin. You want it about 1/4 inch thick. (Not so thin it's falling apart, but not so thick that it will get tough when it cooks.) The pieces will cook down a bit, so make them a little longer and wider than you'd want on a sandwich.
Place sliced pork into a heavy duty ziploc bag. Pour marinade on top. Place in fridge for 4-6 hours.
Once meat has marinated, remove from fridge. Set out a large pot (I used an enameled dutch oven) and pour about 3 tbsp. of vegetable or canola oil on bottom of pan (enough to cover the bottom about 1/4 inch, depending on your size of pot).
Turn heat up to medium high to heat oil. Meanwhile, lay out a large baking sheet lined with paper towels. This will be a great place to set your meat after each batch has cooked in the oil.
Once oil has heated, remove pieces of pork one-by-one with tongs from ziploc bag and slowly place into oil (you want oil to sizzle when you place meat in, but if it pops too much, turn heat slightly down).
Flip meat over to cook both sides evenly. Once edges start to brown, remove from pot with tongs and set on paper towel lined baking sheet.
Sear meat in batches until it's all cooked. Let rest on baking sheet while you assemble the other sandwich ingredients.