8 tablespoons unsalted butter, divided, plus more for baking
1/2 cup maple syrup, divided
4 1/2 cups old-fashioned rolled oats
1 tablespoon baking powder
1/2 teaspoon salt
1 1/2 teaspoons ground cinnamon
3 large eggs
2 cups milk, plus more for serving
1 teaspoon pure vanilla extract
01Preheat the oven to 350 F. Coat 9x13 inch baking dish with butter. Melt 4 tablespoons butter over medium-high heat in large saute pan. Cook, stirring frequently, until butter foams and begins to brown.
02Add apples and 1/4 cup maple syrup. Cook apples, stirring frequently, until they tender and golden brown and most of them liquid has evaporated, 10-15 minutes.
03Meanwhile, whisk together oats, baking powder, salt, and cinnamon in a large mixing bowl. Melt remaining butter and add it to oat mixture along with eggs, milk, vanilla, and remaining maple syrup. Stir until well combined.
04Pour the oatmeal mixture into prepared baking dish. Spoon caramelized apples evenly over the top.
05Bake 30-35 minutes until lightly browned. Serve warm with milk.