Preheat oven to 375 F.
Lightly grease a square 8x8 pan with cooking spray.
In a large bowl, combine oats, flaxseed, brown sugar, cinnamon and salt.
In a smaller bowl, whisk together butter, milk, eggs, and vanilla.
Pour into dry ingredients and stir to combine.
Pour mixture into prepared baking dish.
Bake oatmeal mixture for 10 minutes.
Meanwhile, prep topping. Bring butter, brown sugar and maple syrup to a boil in a small saucepan. Stir in pecans.
Once oatmeal has baked 10 minutes, remove from oven and top with pecan mixture. Return to oven for an additional 10-15 minutes.
Remove from oven and serve warm or let cool to room temperature before covering and refrigerating.
*I used white corn syrup (karo) and added ¼-½ tsp maple flavoring to get maple syrup and also used pecan pieces that I had on hand, just add enough to make it thick with a little bit of syrup juice.