Generate only certain mip levels for UI texture

Hi, I was wondering if there is a way to generate only specific mip levels for a 2D UI texture. The reason for this is that currently, a game I’m working on is loading the smallest mip-level when loading the asset, and then once a widget with the texture comes into view, it loads the bulk-file with all the other mips. However, the only mip that is ever used from the bulk-file is the largest one.
I can’t turn off mip generation all together, as this would cause a lot of memory overhead since every asset will be loaded with its full-sized texture right away.

So my question: Is there any way to only have 2 mip-levels: a mip with the normal texture size, and the smallest mip?

If that is not possible, is it possible to export the texture with only 2 mips, and then use the LeaveExistingMips setting?