Today I made a fresh rhubarb pie. After it had thoroughly cooled my husband and I had a nice cup of tea and cut into the delicious looking pie. Everything was perfect except the filling. It was very very soupy. I have always had trouble thickening fruit pies. I used sugar, flour and 1 egg in the filling for this pie. What do you use to thicken a fruit pie? Do you find that cornstarch, or tapioca is better than flour? I am going to make another one probably tomorrow and I will try a different recipe. Any tips would be appreciated.