To make the batter in a blender, combine the flour, eggs, milk, salt and a few grindsings of pepper in the blender jar, and blend at high speed for 2 to 3 seconds. Turn off the machine, scrape down the sides of the jar, and blend again for 40 seconds.
(To make the batter by hand, beat the eggs and salt with a whisk or a rotary or electric beater until frothy. Slowly add the flour, beating constantly. Then pour in the milk in a thin stream and beat until the mixture is smooth and creamy). Refrigerate the batter for at least 1 hour.
Preheat the oven to 400*. Place the sausages side by side in a heavy 10 to 12-inch skillet, and prick them once or twice with the tines of a fork. Sprinkle them with 2 Tblsp. of water, cover the pan tightly, and cook over low heat for 3 minutes.
Then remove the cover, increase the heat to moderate, and continue to cook, turning the sausages frequently with tongs or a spatula, until the water has completely evaporated and the sausages have begun to brown in their own fat.
Arrange the sausages in a single layer in a baking dish or tin about 6 by 10 inches and 2 inches deep, and moisten them with 2 Tblsp. of their drippings. Keep them at least and inch apart.
Then pour the batter over them and bake in the middle of the oven for 30 minutes, or until the pudding has risen over the top of the pan and is crisp and brown. Serve at once.