Preheat the oven to 350 degrees. Spray an 11 x 7 baking dish with cooking spray.  Set aside.

Heat the butter for the cookie in a skillet over medium heat.  Stir occasionally until it begins to turn a deep brown color, about 5 minutes.  Remove from heat and allow to cool.

Meanwhile, combine the sugar, flour, oats, baking soda, salt, cinnamon, and nutmeg in a large mixing bowl.

Stir the browned butter into the flour mixture.  Add in the egg and mix well. 

Press all but 1 cup of the dough into the bottom of the prepared pan.  Bake for 15 minutes.

Meanwhile, melt the butter for the filling in a small skillet.  When it starts to brown add in the brown sugar and stir until it is almost dissolved.  Add in the evaporated milk and bring to a boil, stirring constantly for one minute.  Remove from heat and add in the vanilla and sea salt if desired.

Arrange the pear slices over top of the baked cookie crust.  Pour the hot brown sugar caramel over top of the pear slices.  Scatter the remaining dough over top of the pears.

Bake for 20-25 minutes or until the topping is golden.  Cool on a wire rack and then cut into bars.

Store in an air tight container for up to 3 days.