After three days the sourdough starter was definitely active, though not to the “vigorously active” stage.
At that point I fed it and put it in the fridge to hibernate while we were away for the weekend.
It seemed reasonably happy when I took it out a few days later, fed it, and let it warm up again in preparation for starting a bowl of waffle batter.
My recipe of choice was King Arthur Flour’s classic sourdough waffles (or pancakes). Luckily waffles get more flavour than leavening from their sourdough content; this meant if my starter really is kind of lackluster it wouldn’t be a big issue. Three minutes turned out to be the perfect cooking time in the flipping waffle iron, and they came out light and crispy, with a bit of sourdough tang.
Half of a recipe made 4 waffles. The leftovers went in the fridge overnight, and crisp up very nicely when reheated in the toaster oven. I’ll definitely make these again and try the pancake version as well.