Couldn’t you use UTM to run a macOS VM?

All the sibling comments appear to have missed your requirement of running Big Sur (macOS 11) --- everything based on Virtualization Framework is "paravirtualisation" and requires cooperation between the host and guest.

You could run the amd64 version of macOS 11 in QEMU on the M1, but that's ARM-to-x86 emulation, which will be slow, and I suppose isn't what you're looking for.

Checkout tart: https://tart.run/quick-start/

It uses Apples Virtualization framework and works well, besides issues with virtiofs. But those can be worked around with virtual block devices aka images.

Try VirtualBuddy https://github.com/insidegui/VirtualBuddy

Have you run into Viable https://eclecticlight.co/virtualisation-on-apple-silicon/ or VirtualBuddy https://github.com/insidegui/VirtualBuddy ? I think at least Viable has some limitations though

Edit: "some" limitations is putting it lightly. From https://eclecticlight.co/2022/11/17/lightweight-virtualisati... which is apparently still current:

> Apple’s current implementation of lightweight virtualisation still has no support for Apple ID, iCloud, or any service dependent on them, including Handoff and AirDrop. Perhaps the most severe limitation resulting from this is that you can’t run the great majority of App Store apps, although Apple’s free apps including Pages, Numbers and Keynote can still be copied over from the host and run in a guest macOS.

Same deal with VirtualBuddy, apparently the root of the problem is that some sort of hardware validations fail in VMs https://github.com/insidegui/VirtualBuddy/discussions/27