Grease a bread pan. No, grease it more. Seriously, this thing sticks like fuck. Preheat the oven to 180C/350F.
Put the cranberries in the boiling water while you get everything else together. Mix the dry ingredients in a large bowl. Peel the oranges and mince the peels, then slice the oranges across the segment boundaries so you get little orange triangles that come apart easily. Throw all that in the bowl with the dry ingredients.
Upend the water and cranberries into the bowl with the dry ingredients, then add sour cream, butter, aquafaba, and vanilla extract. This will not be a runny batter! Mix it until you’ve got no lumps that aren’t fruit. Scrape it all out into the greased pan.
Bake for about 1h 15m. It may take a little longer, depending on your oven, but you might want to drop some foil over it in the last 10 minutes, if it starts getting too brown on top.