Update: I am safely past the scalding stage! Whew! Now I am worrying that doubling the recipe was a mistake, and will exceed the capacity of my mixer.
Update 2: Okay, so I couldn't take photos for most of the process because I had to pay too close attention (couldn't even watch tv!). But at this stage, there were 12 minutes of waiting. Doubling the batch was JUST within my mixer's capability without flowing over the top of the whisk attachment.
Update 3: But all's well that ends well. Although, whew -- doubling the peppermint extract means that these marshmallows are not for the faint-of-peppermint-heart! Now they set for a few hours, and then I try to remember how to cut them. Oiled knife? I hear scissors can also work�
Note: Either my kitchen now REEKS of peppermint, or the scent of the extract has seeped its way into my brain�