In a large pot place the onion, tomatoes and tomatillos. Add enough water to cover the ingredients. Place the pot over medium heat and allow the ingredients to cook until soft. Keep an eye on the tomatillos, we don’t want them to burst (see notes). 

Meanwhile, toast the chiles de arbol on low heat, just until they turn fragrant. Rinse and set to the side until we need them. 

When the tomatillos turn pale green, cooked through and still whole, remove from the boiling water. Allow the rest of the ingredients to soften and finish cooking. Additionally add in the toasted chiles de arbol to soften and rehydrate. Remove the ingredients  from the water when ready and let them cool down. 

Pat dry the block of cheese and dice into bite size pieces.

Place a non stick pan or griddle over medium heat and add about 1 TBSP of oil. Brown all the cheese until golden. Add oil as needed. Remove from the heat when ready. 

Dice the steak into bite size pieces. Season with salt and pepper to taste. I used 2 tsp of kosher salt. Mix to evenly season the meat. 

For the salsa: place the cooked onion, tomatoes, tomatillos and chilis in a blender. Additionally, add the garlic cloves and Blend until smooth. (We will add the salt later on)

Place a large pan over medium high heat and add about 3 TBSP of olive oil. Once hot but not smoking, add the beef cuts. Make sure you don’t over crowd the pan. Sear and brown the meat on all sides. Remove when ready and do the same with the rest of the meat. Add oil as needed. 

When all the meat is done, lower the heat to medium low and pour in the tomatillo salsa. Gently stir as the browning at the bottom releases right into the salsa. Let it cook for about 5 minutes on a gentle simmer, this way it does not reduce too much. 

Meanwhile in a large pot combine the meat and cheese. When the salsa has had enough time to cook, stir in salt to taste and combine with the meat and cheese. 

Cover and cook on a gentle simmer over medium low heat. During this time the meat will finish cooking and the cheese will soften, (about 5 minutes). Uncover and taste, add salt if needed. Remove from the heat and serve. 

You can accompany with Mexican rice and a fresh salad.