Heat oil in a medium-sized pan, sauté beef until it turns brown. Add onion and garlic and continue sautéing.
Once the onion and garlic are aromatic, add cumin powder, chili powder, smoked paprika and Worcestershire sauce. Stir well. Season with salt and pepper to taste. Turn off the heat and set aside.
For the Salsa Filling:
Mix all ingredients and season with salt and pepper to taste.
Preheat oven to 350⁰F/177⁰C. Grease and line 3 oz muffin tins. Set aside.
For the Egg Muffin Mixture: In a clean bowl, mix eggs, milk, and flour. Add salt and pepper to taste.
Pour 2 tablespoons of the egg muffin pan to each individual muffin holes. Add 1 to 1 ½ tablespoons of the meat filling, then topped it up with the salsa filling. Then pour 2 to 3 tablespoons of the egg muffin mixture or until the individual muffin holes are full.
Bake the Mexican Breakfast Muffins for 15 to 20 minutes or until done.
Remove muffin pan from the oven and let it cool in a cooling rack. Topped with chopped chives and serve.