Take the pork out of the fridge 30 minutes before starting. This helps it cook evenly later. While waiting, prepare your marinade ingredients and get your tools ready.
Slice your pork butt into thin pieces, about ¼-inch thick. Cut against the grain – this means cutting across the meat lines, not parallel to them. Your slices should look like little rectangles, not long strips. If some pieces are thicker than others, gently pound them with a meat mallet until they're even.
Mix your marinade in a bowl: combine sugar, salt, garlic powder, black pepper, and red food coloring if you're using it. Add your sliced pork and massage everything together with your hands for 5 minutes. Really work the marinade into each piece of meat. Every slice should be well-coated with the mixture.
Put your marinated meat in a container with a tight lid or a zip-top bag. Place it in the refrigerator and let it cure for at least 8 hours, but overnight is best. Don't leave it for more than 24 hours.
When you're ready to cook, take out your marinated pork and put it in a pan. Add 1 cup of water and turn the heat to medium. Let it simmer with the lid on until the meat is tender and most of the water has evaporated – this usually takes about 15-20 minutes.
Once most of the water is gone, add 2 tablespoons of cooking oil. Keep cooking and stirring until the meat starts to caramelize and turn golden brown around the edges. This should take about 5-7 minutes. You'll know it's done when the edges are slightly crispy and darkened, but the meat is still juicy inside.
Let your tocino rest for 5 minutes before serving. This keeps the meat juicy. Serve hot with garlic fried rice and a sunny-side-up egg for traditional tocilog. Don't forget to put some chopped tomatoes and vinegar on the side.
For any leftovers, let them cool completely before storing. They'll keep in the fridge for 3-4 days. When you want to reheat, just add a tiny splash of water to the pan to keep the meat moist while it warms up.