1. In a large bowl, whip the cream until stiff peaks form. Fold in the maple syrup. Cover with plastic wrap and refrigerate up to 3 days.
2. In a large bowl, beat the butter with an electric mixture on medium speed until light and fluffy, about 30 seconds. Beat in the brown sugar.
3. In a medium bowl whisk together the flour, oats, baking powder, cinnamon, baking soda, and salt. Add the flour mixture to the butter mixture and beat until well combined. Add the milk and eggs. Beat until just combined.
4. Spread about 2 Tbs. batter onto a hot, lightly greased griddle or heavy skillet. Cook over medium heat for 2 to 3 minutes or until golden brown and bubbles form on the surface of the pancake. Turn and cook 1 to 2 minutes more or until golden brown. Repeat with remaining batter. Let cool.
5. To assemble the cookie pies: Place one pancake on a plate and cover with about 2 Tbs. maple whipped cream. Sandwich with a second pancake. Repeat with remaining pancakes and cream.