Can I substitute 1 tsp of vanilla extract for the whole bean and the extract as the recipe calls for? Also, how much salt should I add to my butte...

Hi Megan!
On the vanilla - the bean (especially that much) will give a much richer flavor than extract. Also, if you're adding it to a custard, it will provide those pretty black flecks, and maybe even a bit of texture. If you can find it, I'd go with the bean!

Generally, I find it strange that a baking recipe calls for unsalted butter, however, if I were making this recipe, I'd just add a heavy pinch, so approx. ½ t. I like my salt, though. As for the vanilla extract, It is nearly always an acceptable substitution for a bean. If you can source vanilla paste, that is an even better substitution.