1. For the crust, remove the filling from the Oreo cookies and crush the cookies. Add melted butter and mix well. Press and spread the crust into a pan.
2. For the filling, peel, slice, and steam sweet potatoes until soft. Use a blender to puree sweet potatoes to make 4 cups.
3. Add sweetened condensed milk, butter, and vanilla to the sweet potatoes and blend well. After mixture cools, add eggs, and blend well.
4. Spread filling into crust and bake in a toaster oven at 200 degrees Celsius between 20 and 25 minutes with both upper and lower heating elements on. Do not over cook.
5. Pie is done when top turns brown. May eat warm or cold.