Heat a medium saucepan over medium heat. Add the millet to the dry pan and toss until lightly browned, stirring often. Add water and a pinch of salt. Bring to a boil, cover, and lower to a simmer. Cook for 15-20 minutes (20 minutes works for me), until water is absorbed. Remove from heat and allow to sit covered for an additional 15 minutes. Fluff with a fork and use immediately or refrigerate for up to 5 days.
Preheat the oven to 375 degrees. Butter an 8-inch square or 9-inch round baking dish.
Mix the baking powder, cinnamon, nutmeg, ½ teaspoon sea salt and orange zest in a large bowl. Add the maple syrup, milk, eggs, melted butter, and vanilla and whisk until combined. Stir in the millet and ¼ cup nuts. Add the coconut, raisins, shredded apple, diced pineapple and shredded carrots and mix to combine well.
Transfer to the prepared pan. Sprinkle the remaining ¼ cup nuts over the top. Refrigerate up to overnight or bake right away.
Bake for 50-55 minutes or until the millet mixture is set and wet ingredients are absorbed.