Preheat oven to 400 degrees F.
Cut the stem off the cabbage so it can sit flat in the pan.
In a medium bowl, whisk together melted butter, mustard, maple syrup, Worcestershire sauce, garlic powder, smoked paprika and season with salt and pepper. Stir the mixture and set aside.
In a large bowl, combine celery, carrots, onion, oil, and all the chopped herbs. Season with salt and pepper. Toss to combine.
Place the veggie mixture in a large, cast-iron skillet.
Place the cabbage in the center, on top of the vegetables. Brush the cabbage all over with half the maple butter mixture. Pour half of vegetable broth into the bottom of the pan and cover cabbage with aluminum foil.
Bake for 45 minutes, remove the foil and brush the cabbage with the remaining maple butter mixture.
Add remaining vegetable broth and bake until cabbage is tender and slightly charred, about 45 minutes more. To check if the cabbage is done, pierce it with a fork and see if its tender.