Preheat oven to 400 F. Grease muffin pan.
Cook bacon to desired doneness. Cook it crispier than you would normally eat it, as it will soften some while the muffins bake. Drain on a paper towel and dice.
In a small bowl, combine milk and apple cider vinegar. Let sit for 5 minutes. If you have buttermilk on hand, skip this step and use a cup of that instead.
In the meantime, combine blue corn meal, flour, sugar, baking soda and salt in a separate bowl. Stir in the diced bacon and the chopped green onions.
Add the milk mixture (or buttermilk), melted butter, beaten egg, and Hatch green chiles. Combine well.
Distribute muffin mix evenly into greased muffin pan. The bacon tends to sink to the bottom so stir often to distribute evenly.
Bake on the middle rack for 10-12 minutes, or until a toothpick inserted into the muffin comes out clean.