Heat the oven to 400°F.
Melt the 1 tablespoon butter in a small saucepan (or in a small bowl over low heat in the microwave).
Once cooled add 1 tablespoon brown sugar and 1/2 teaspoon cinnamon and then set aside.
Slice the pears in half from top to bottom (the long way).
Core the pears but using a melon baller or grapefruit spoon.
Spray a thin layer of cooking spray over the inside of a baking dish.
Place the pears in the baking dish, flat side up.
With a pastry brush, brush the pears with the melted butter and brown sugar mixture.
Cover the baking dish with tinfoil, and bake for 20 minutes.
Cut the remaining tablespoon of butter into cubes.
Add it to a bowl, along with 2 tablespoons brown sugar, 1/4 teaspoon cinnamon, flour, oats, and a pinch of salt.
Use a fork to blend the ingredients together.
After the pears have finished baking, remove the baking dish from the oven.
Use a fork to carefully spread the oat mixture over top of the pears.
Increase the oven temperature to 425°F.
Place the baking dish back in the oven and bake, uncovered, for 15 minutes more.
Remove the baking dish from the oven.
Cool the pears for about 5 minutes before serving.