PREHEAT oven to 350. BEAT the eggs on high speed for 5 minutes. Gradually beat in sugar,pumpkin and lemon juice. Mix in remaining ingredients. Line cookie sheet with foil.
GREASE and flour tin foil or use cooking spray. POUR mixture into pan. Top with walnuts and BAKE at 350 for 20-25 minutes.
REMOVE from oven when toothpick inserted into cake comes out clean. LAY a kitchen towel (I use a white flour type) on counter (fold to double thickness) slightly larger than size of cake pan.
SPRINKLE towel with one cup of powdered sugar. While cake is quite warm, turn cake upside down on the sugared towel. ROLL up cake along with the towel from end of cake. COOL. UNROLL and spread with filling.