Turn your slow cooker / crockpot to high and preheat while you deal with meat. I add a little bit of olive oil to slow cooker and coat bowl using a pastry brush, but this is optional.
Cut your steaks into single portions (approx 3-4 inches long), coat in flour. Turn up the heat in a saucepan, add a squirt of oil and add your beef / prefered meat. Sear until meat is sealed.
Add meat to your slow cooker. Add the 1/2 cup of water (cold is fine) and cook on high for 1 hour.
Once the first hour is up, turn slow cooker down to low and leave for 5-6 hours.
Once cooking is done, take meat out of slow cooker. Drain liquid, leave slow cooker on low (or high if you want to speed things up). Using a fork shred steaks up into bite sized pieces. The meat should shread very easily and be very tender.
Place meat back into slow cooker, add your favourite taco / burrito seasonings (I just use 1 or 2 of my favourite taco sachets from supermarket), add a little water to desired consistancy. Leave on for approx 45 mins.
Serve hot in tortillas with your favourite toppings.
Please note: You can use this method for shredded bbq meat for burgers too, switch out the taco seasonings, and add your favourite bbq sauce after 5-6 hour mark.
Also note: I often ignore the cooking times for low / high. Rule of thumb is for every hour on low, the cooker can do on high in 30 mins. So just adjust to whatever time you have in your day.