1tablespoonboiling water mixed with 1 tablespoon instant coffee
Preheat oven to 100C fanbake.
Using handheld beaters, or a stand mixer, start whipping your aquafaba. It will start to foam and thicken. Start gradually adding sugar, and keep beating. After about 10 minutes you'll have very thick, glossy meringue. Just like egg white meringue. Then add your vanilla paste, white vinegar and cornflour.
I'm unsure whether the cornflour and white vinegar are necessary, but saw a lot of failed experiments on the internet so it seemed like a good idea to stabilise the mixture. It was so thick it hardly seemed it would need it, but I wasn't sure what would happen when it was cooked.
Swirl through about half of the coffee mixture, being careful not to overmix.
Pipe or dollop spoonfuls onto a lined baking tray and pop in the oven.
Bake for about 2 hours, then cool in the oven. Mine still had a little chew in the middle, which while not at all unpleasant, wasn't what I was going for. So if you're after crispy meringue the whole way through, maybe try baking for 2.5 hours.