Fleece glomits under mountaineering mitten shells.

For the really cold days (less than -10 Fahrenheit) I wear thin fleece gloves under glomits under mountaineering mittens. Inside the flap of the glomit I have sewed a merino wool pocket which essentially doubles up the mitten part.

I wear the glomits because it allows me to use my fingers when I need to, which is mostly just locking and unlocking my bike. The mountaineering mittens are bunjee corded to my arms like a preschooler so I don't drop them. This system has worked great for a number of years.