1. Cream butter and sugars together until light and fluffy, about 3-4 minutes.
2. Mix in egg and vanilla extract.
3. Add cinnamon, flour, cornstarch and baking soda to a medium sized bowl and combine.
3. With the mixer on low speed, add flour mixture to butter and sugar mixture.
4. Stir in old fashioned oats and raisins. Dough will be thick.
5. Chill for at least 30 minutes or overnight. I very much recommend overnight.
6. When ready to bake, preheat oven to 350 degrees.
7. Place parchment paper into the bottom of your 9 inch cake pan to help the cookie not stick.
8. Spread the dough out into the cake pan. Bake for 22-25 minutes or until the edges are slightly golden. The center may not look completely cooked, but it is.
9. Remove from oven and allow to cool completely in the cake pan. Be careful of removing the cookie cake from the pan too soon. If it hasn’t cooled enough, the center will be very soft and easily breakable. I let mine cool for at least an hour before removing.
CINNAMON MAPLE ICING:
1. Beat the shortening and butter together until smooth.
2. Slowly add powdered sugar. Mix until combined.
3. Mix in the maple extract and cinnamon as well as desired amount of water to get the right consistency.