1. Preheat oven to 350Â° F.
2. In a large skillet, add oil and sautÃ© onion and sweet potatoes until the onions are transparent and the sweet potatoes are limp.
3. Add a few drops of water if necessary to prevent scorching.
4. In a blender, place 1/3rd of the sweet potato mixture and beans; process on low speed until smooth.
5. Return the blended bean mixture to the skillet along with the remaining sweet potatoes.
6. Stir in the egg and season with spices.
7. Into the pie crust, pour the sweet potato mixture.
8. Place the pie crust in the oven and bake for 40 minutes.
9. Serve immediately.