vanillin is sold in some parts of europe in packets. At least in italy, it is a chemical fake vanilla, and has a strong aftertaste. As far as i know, vanillin is the closest thing chemically to real vanilla, that is, closer than other fake flavorings are to what they are supposed to resemble, and if you read italian ingredient lists for commercial cakes and sweets, often they have "artificial flavoring" written in english and "aromi naturali" (natural flavoring) in italian! Apparently, since the molecule is so close to vanilla, they allow it as a natural flavoring. However, i can taste it and find it disturbing. You can replace a tsp or two of vanilla extract for a pck of vanillin. Unfortunately, there is no other vanilla here, even in pastry supply stores, you can either buy real vanilla bean or this chemical stuff. I;ve used it but prefer real extract, so i usually bring a big supply from abroad. You can taste the difference more in creams - in cakes it can be less noticeable. Anyway, to adjust the recipe, just put in a tsp or so vanilla extract. It';s not one of those ingredients nthat have to be perfectly measured. (i usually just dump some directly from the bottle without measuring.)
The baking powder pkgs weigh 15 gms. If you know how many grams in a tsp, you can figure out the equivalent in tsps. I have used it interchangeably with canned baking powder, teaspoon for teaspoon, and it works fine, so it must be the same mixture.
"Siduri said, 'Gilgamesh, where are you roaming? You will never find the eternal life that you seek...Savour your food, make each of your days a delight, ... let music and dancing fill your house, love the child who holds you by the hand and give your wife pleasure in your embrace.'"