Place the chicken pieces in a medium bowl and season them with salt, pepper, and granulated garlic; set aside.
In a large nonstick skillet, heat 2 tablespoons of oil. Sauté the onion and garlic until golden brown, about 2 to 3 minutes. Transfer them to a plate and let them cool.
In the same skillet, heat 2 tablespoons of oil over medium-high heat. Add the chicken pieces and cook until they are golden brown and cooked through about 8 to 10 minutes. You might need to do this in batches, depending on the size of your pan.
While the chicken is cooking, prepare the chipotle sauce. In a blender or food processor, combine the chipotle peppers, 3 tablespoons of the adobo sauce, half of the milk, cheese, and the cooled sautéed garlic and onion.
Blend the mixture until it reaches a smooth consistency. Stir in the remaining milk to cool down the chicken and prevent curdling. Pour the chipotle sauce over the cooked chicken in the skillet.
Place the skillet over low heat, allowing the sauce to simmer gently, about 2 to 3 minutes. Don't let it boil, as this can curdle the sauce. Then remove from heat and serve.