Preheat the oven to 425F Select a pan or dish that will hold between 2-3 quarts. Place the butter or margarine in the pan/dish and set in the preheated oven. Work quickly to make the batter. Place the eggs in a blender and blend on high for 1 minute. Keep motor running and slowly add the milk, then the flour and continue to blend for 30 seconds. You can also use a bowl and a hand mixer. Immediately pour the batter into the hot pan/dish over the melted butter. Bake about 20 - 25 minutes until puffed up and golden and batter is cooked through. Bring to the table to serve. Squeeze fresh lemon all over the pancake and sift powdered sugar over the top. Cut into quarters and serve with extra sugar and lemon wedges.