Remove the skin from the drumstick before rinsing each one under some cold water. Pat drumsticks dry with a paper towel.
In a large bowl combine dry mustard, crushed garlic, salt, pepper, lemon juice, lemon zest and olive oil and mix well. Place drumsticks into the marinade and coat well (you can do this in a Ziploc bag to make things easier). Cover and pop in the fridge for at least two hours and no longer than twelve hours.
When ready to cook, preheat oven to 375 degrees. Place drumsticks in a small casserole dish and bake for about 45 to 55 minutes, or until done (temp should hit 165). The juices should run clear when pierced with a knife. Enjoy!