01 - Preheat oven to 350°F (175°C). Generously grease a 9x9-inch baking dish to prevent sticking.
02 - In a large mixing bowl, thoroughly combine rolled oats, chopped nuts, baking powder, ground cinnamon, nutmeg, and salt.
03 - In a separate bowl, vigorously whisk together milk, eggs, melted butter, maple syrup, and vanilla extract until fully incorporated.
04 - Pour the wet ingredients into the dry mixture. Stir gently until evenly moistened and just combined.
05 - Fold diced apples and dried fruit into the oatmeal batter, ensuring even distribution.
06 - Spread the mixture evenly in the prepared baking dish. Place in oven and bake for 35 minutes, or until the top is golden brown and the center is set.
07 - Allow bake to cool for 5 minutes before slicing. Serve warm, optionally topped with extra milk or yogurt.