Line 2 baking sheets with parchment

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Make the Ermine Frosting

1. If you haven’t already, make a batch of Ermine Frosting

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   . 

Make the Oatmeal Cookie Dough

1. Cream the butter with the sugars on low speed (Kitchen Aid

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   1 or with a hand mixer) until very well blended and fluffy. Scrape down the sides of the mixer several times.
2. While the butter is beating, mix the dry ingredients: in a large bowl, mix the flour, oats, baking powder, cinnamon, and salt with a whisk. Add in the chopped white chocolate and cranberries, then toss them well to distribute them in the dry mix.
3. When the butter mixture is fluffy, add in the eggs, one at a time, along with the molasses, if using. Add in the vanilla and beat for a few more seconds.
4. Scrape the bowl and beater well, paying attention to the bottom of the bowl which always likes to hide a little pocket of unmixed butter.
5. After you’ve finished scraping, pour in the dry ingredients (the mixer should be off!). Lower the mixer paddle into the whole mix, then carefully turn the mixer on then off rapidly. If you make this on/off motion in one little microsecond burst at a time, the flour won’t go everywhere. After a few power pulses, the mixer should be able to mix everything without flinging flour. Mix just until you see no flour–about 10 seconds.
6. Place scoops of dough onto a sheet tray.  Chill the dough balls for 30 minutes.

Bake the Cookies

1. When you’re ready to bake, preheat the oven to 350 F (180C).
2. Place 8 balls of dough on a sheet, leaving plenty of room between cookies.
3. Bake two prepared sheet pans of cookies for 15-16 minutes, rotating the sheets 180 degrees and swapping them from top to bottom halfway through baking for the most even baking.
4. Allow the cookies to cool about 5 minutes on the sheet pans before moving them to a rack to completely cool.
5. Bake extra dough on cooled sheet trays. If they’re too hot, you can place them in a cool table outside, or stand them vertically against a cabinet for a couple minutes.  Cool all the cookies completely before sandwiching them together with frosting.

Filling the Cookies

1. If you’re working with cold Ermine Frosting

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   , take the frosting out of the fridge and let it sit for 10-15 minutes before whipping it into a soft frosting that will be easy to spread.
2. Scrape the frosting into a pastry bag fitted with a plain tip.
3. Squeeze a spiral of frosting onto the backside of a cookie.
4. Press a second cookie over the frosting to make a cinnamon oatmeal cookie sandwich. Repeat the process for the rest of the cookies.

Storing Oatmeal Cream Pies

1. Place sandwiched cookies into the fridge in a closed container.  They will keep in the fridge for up to 1 week. 
2. The cookies can also be frozen in Ziploc bags or individual cookie bags inside a Ziploc for up to 3 months.
3. For a lunchbox treat, place a frozen cookie into a chilled lunchbox.  By lunchtime, it will be the perfect temp for eating!