01 - Preheat oven to 350°F (175°C). Grease a 9x9-inch baking dish thoroughly.
02 - Combine rolled oats, chopped nuts, baking powder, ground cinnamon, nutmeg, and salt in a large mixing bowl.
03 - In a separate bowl, whisk together milk, eggs, melted butter, maple syrup, and vanilla extract until well blended.
04 - Add the wet ingredients to the dry ingredients and stir until fully incorporated. Gently fold in diced apples and dried fruit.
05 - Pour mixture into the prepared baking dish, spreading evenly. Bake for 35 minutes until the top is golden brown and center is set.
06 - Allow oatmeal bake to cool for 5 minutes before serving. Serve warm, optionally with extra milk or yogurt.