In the past, I've patiently increased the recipe's instructed temperature by 10 degrees (F) each time. But
according to the Hummingbird Bakery Blog, Banana and Chocolate cupcakes are especially prone to cratered cupcakes in the first place. Each batch's bake time will depend on how ripe the banana used in the recipe is; the riper the banana, the more sugar and moisture in the fruit. More sugar and moisture = a longer bake time.
Since I had used a fairly ripe banana for this batch, I was pretty sure that a 10 degree (F) increase (from 325 to 335) wouldn't be enough. I decided to notch it up by 20 degrees (F) and see what happened: