01 - Preheat the oven to 350°F (175°C). Grease a 9x9-inch baking dish to prevent sticking.
02 - In a large mixing bowl, blend rolled oats, chopped nuts, baking powder, ground cinnamon, ground nutmeg, and salt until evenly distributed.
03 - In a separate bowl, whisk together milk, eggs, melted butter, maple syrup, and vanilla extract until thoroughly combined.
04 - Pour the wet mixture into the dry mixture and stir until just combined. Fold in the diced apples and dried fruit for even distribution.
05 - Pour the resulting mixture into the prepared baking dish and spread evenly using a spatula.
06 - Bake in the preheated oven for 35 minutes or until the top is golden brown and the oatmeal bake is set at the center.
07 - Remove from the oven and let cool for 5 minutes. Serve warm, optionally with a splash of milk or yogurt.