Me thinking. Next sat me brew a stout. But i am out. Of vanilla beans. And my vanilla conection guy. Stuck in colombia. Due to corona. So i am thinking. Iam gonna use. Vanilla extract. So ratio. 1 bean. Equals. 1 tbs. Of vanilla. Extract. ??? And. Proberly. This extract. Stronger flav. Than. Beans. When should i add. Normally. Me add 4 beans. 10 days before kegging
1 bean equals 1 to 3 teaspoons according to my googling. I guess the quality of the ingredients varies to such a large degree that there is no perfect answer.
As @squeegeethree said the quality of the extract is key, which makes it difficult to have a definitive equation.
If I was using extract I would add it to the keg.