Set to lowest speed and add milk and then flour.
Blend all ingredients on highest speed for 30 seconds.
Take dish out of oven and put in butter. Make sure butter melts completely and coats entire baking dish.
Pour in the batter and then Bake at 425 degrees for about 20 minutes until puffed up and golden brown around the edges and in the middle (I start checking it around 16 minutes just to make sure not to overcook it).
Now you have a wonderful breakfast or brunch item we call the PET (Puffy Egg Thing).