Preheat the oven to 350 degrees F (175 degrees C).
Mix oats, brown sugar, baking powder, cinnamon, and salt together in a large bowl.
Whisk milk, butter, eggs, and vanilla extract together in a separate bowl. Combine with the oat mixture and stir in cranberries, pecans, and white chocolate chips.
Bake in the preheated oven until set, 40 to 45 minutes.