Dynamic mipmap creation?

I am creating some textures at start up right now which will not be edited later on during gameplay.
This is working fine with some help from

But my issue is now how to create more mip levels? When I create the texture it only starts with one miplevel.
I tryied to simply just adding one in the texture->PlatformData->Mips array, but that ofcourse ended with a crash.
Any help on how to create mipmaps for a dynamic texture or either getting it auto generated would be greatly appreciated!

Thank you!