Preheat your oven to 375 degrees and GENEROUSLY spray a muffin pan with cooking spray.
In a large frying pan, heat the olive oil over medium-high heat.
Add in the ground beef and cook, breaking up, until no longer pink. Add in the taco seasoning and stir until well mixed.
Remove the pan from the heat and stir in the salsa. Set aside.
In a large bowl, whisk the eggs and egg whites with a pinch of salt and pepper.
Using a ladle, divide the eggs between 12 muffin cavities.
Divide the beef mixture between the cavities, which is about 2 Tbsp per cavity.
Finally, top each muffin cavity with 1 lightly heaping Tbsp of the cheese.
Bake until the eggs are set and lightly golden brown, about 20-23 minutes.
Let cool in the pan for 10 minutes and them remove to a wire rack to finish cooling.