Toss the cubed pork with the chili powder, garlic, sea salt, and pepper.
In a large dutch oven, brown all sides of the pork in the olive oil on medium-high heat. (I usually have to do this in two batches.)
Then add the chicken broth and water to the pork and bring to a boil.
As soon as it comes to a boil, turn the heat to simmer (low) and cover with a tight fitting lid.
Simmer for about 2 hours, until the pork easily falls apart.
Remove the lid and remove 1/2 cup of the juices and set aside.
Discard almost all the rest of the juices, while just leaving enough to coat the bottom of the pan.
On medium heat, allow the pork to caramelize on the bottom of the pan.
Once the pan is dry and the meat is stuck to the bottom of the pan (yes, this is a good thing!), add your reserved juices to the meat and scrape the meat off the bottom of the pan...along with all the blackened flavor bits! (This is what makes it taste so good!)
I usually add a little more salt (to taste) and shred the meat.
You can squeeze a lime over the meat and serve with warm tortillas.
Garnish with cilantro and avocados.
