Put the mozzarella and cream cheese in a microwave-safe bowl. Microwave for one minute. Stir. Microwave for 30 seconds. Stir. At this point, all the cheese should be melted. Microwave 30 more seconds until uniform and gloopy (it should look like cheese fondue at this point).
Add the rest of the dough ingredients and the cheese to a food processor. Mix using the dough blade until a uniform color.
Grease a 24-hole mini muffin tin. Divide the dough between the holes of the tin. Using wet fingers, press it down into the bottom and up the sides of each hole. If your fingers aren’t wet, it will stick to your fingers. I keep a small bowl of water next to me while I work. I dip my hands, press two out, dip again, and repeat.
Filling
Combine the eggs, cream cheese, onion, garlic, and salt in a blender or food processor. Blend until smooth.
Assembly
Preheat the oven to 350.
Add a little cheese and meat or vegetable to each dough cup. Fill with the egg mixture. Bake for 20 minutes or until golden and puffed.
Notes
Dough - If you do not have a food processor, you can mix in a medium bowl with a wooden spoon, but you may need to dump it onto wax paper and knead it by hand to thoroughly incorporate the ingredients.Extra Filling - If you have any egg mixture left over, bake it in a greased ramekin. Depending on the additions you choose, there may be some left.