Change the Surface to Solid for the cake container.
The steps are:
1. Create a surface sweep for the lip and base position.
2. Connecting lip and base with the lofted surface.
3. Create a planar surface on base.
4. Create a profile surface.
5. Trim surface.
6. Knit surface for all surfaces.
7. Thicken surface for change to solid.

Have a nice day

  1. Step 1: