Marjoram is a type of herb that is often used in cooking to add flavor to dishes. It has a mild, sweet aroma and taste, similar to oregano. Full definition
Or try adding 2 teaspoons of marjoram with the peppers. (whats4eats.com)
I can't help tinkering though and I substituted half of the flour with whole wheat flour and included fresh marjoram in the filling. (smittenkitchen.com)