Lightly coat a silicone muffin pan with cooking spray and set your oven to preheat at 350℉. Combine the eggs, cottage cheese, cheddar, salt, and pepper in a blender and blend until the mixture is velvety smooth; a compact blender works well for this. Pour the blended mixture evenly into the muffin cups, filling each one halfway. Scatter the chopped chives over the top, adding any extra fillings such as vegetables or cooked bacon if desired. Bake for 20–22 minutes until the centers are just firm to the touch. Take the pan out of the oven; the egg bites will appear puffed but will gently settle as they cool. Allow them to rest briefly before removing them from the pan to serve immediately or store for later enjoyment. Keep any remaining bites in a sealed container in the refrigerator for up to 5 days.