In a large mixing bowl, cream together butter and brown sugar.
Add in egg and vanilla and mix well.
Add flour and baking soda and mix until completely incorporated.
Fold in M & M's.
Spread batter into a 9-inch pie pan sprayed with nonstick cooking spray.
Bake for 25-30 minutes, or until a toothpick comes out clean.
Let cool and cut into slices.
Top with a scoop of ice cream and drizzle of chocolate syrup.
Notes
We love to put a scoop of vanilla ice cream on top of a slice of this cookie pie and drizzle a little chocolate syrup on top, but that is totally optional. (Ice Cream and Chocolate Syrup are included in Nutritional Information)