Dissolve The Yeast In The Water, Add It To The Flour, And Mix Well. Let The Mixture Stand At Room Temperature Overnight. (In Winter It Takes 2 Days To Allow Fermentation.) Stir In The Baking Powder And Let The Mixture Stand For 10 Minutes. Put About 1/2 Teaspoon Oil In Large Skillet, Add About 1/2 Cup Of The Batter, And Fry Over Low Heat For 1 Or 2 Minutes. When Bubbles Appear, Cover The Skillet For 15 Seconds. Turn Out The Pancake To A Dish. Prepare All The Pancakes This Way, Frying On One Side Only.