How can I avoid an underbake in a bundt pan?
If in doubt, a cake, unless it has a very sticky filling (fruit+sugar, chocolate...), can almost always be tested by pushing a toothpick/skewer right through the center (while in opened oven - oven gloves advised if inexperienced :), and checking whether the stick comes out clean - if not, give it extra baking time. If the exposed surface would brown too much by doing that, cover with aluminium foil.