To determine how many cups of flour you should use with 6 teaspoons of vanilla, we would need a specific ratio or recipe that corresponds the amount of vanilla to flour. Without that information, a specific answer can't be given. However, a common ratio in baking could be, for example, 1 teaspoon of vanilla per cup of flour. In that case, using 6 teaspoons of vanilla would correspond to 6 cups of flour.
If you have a specific recipe in mind or a particular ratio, let me know!