Place the meat in a large, deep skillet with 2 cups water and 1 1/2 tsp salt.

Bring to a boil over high heat.

Turn heat to low and cover with a lid.

Simmer for 1 hour and 45 minutes.

Remove the lid and turn the heat back up to med/high.

Cook until all but about 1/4 cup of the liquid renders out.

Remove the meat from the pan and set aside.

Remove the fat and browned bits from the pan and reserve.

Place 1 tbsp of the fat and browned bits back in the pan along with the sliced onion.

Cook until caramelized.

Add the tablespoon of lemon juice and 1/4 cup water to deglaze the pan.

Remove the onions and set aside in a bowl with a lid to keep warm.

Add 1 tbsp of the reserved fat and browned bits back to the pan along with the beef chunks.

Smash the beef with a potato masher to break into shreds.

Add the rest of the seasonings to the pan along with 1/4 cup water and incorporate well.

Warm through on low heat.

Taste and season with salt and freshly ground black pepper to taste, if needed.

Cover with a lid and turn the heat off.

Serve the beef on fresh warmed tortillas along with the caramelized onion and your favorite garnishes.