Moist and chewy, high altitude tested oatmeal cream pie bars made with browned butter and a hint of spice, frosted with vanilla icing and sprinkled with candied ginger. These taste just like oatmeal cream pies, only so much better!
You might also love these high altitude recipes for oatmeal scotchies, old fashioned iced oatmeal cookies, and chocolate chip oatmeal cookie bars.
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Why You’ll Love This Recipe
Brown Butter and Spice. The oatmeal cookie recipes on my site have been favorites with those of you who follow my site, especially these homemade oatmeal cream pies and old fashioned iced oatmeal cookies. And what’s not to love? Oatmeal cookies are buttery and chewy, moist when they’re not over-baked, and pair beautifully with spices. Today’s oatmeal bars have brown butter, a hint of molasses, and warming spices like cinnamon and ginger for the perfect amount of sugar and spice. The candied ginger sprinkled over the icing adds a little more spice, and it’s such a nice contrast to the sweet vanilla icing.
No Mixer Needed. You won’t need a mixer to make the cookie bars or the icing, just a bowl and whisk.
Perfect for Summer Parties. I love taking a bar dessert to summer parties and bbqs. And while I usually make these s’mores chocolate chip cookie bars for the 4th of July, this year I have plans to make a double batch of these oatmeal cream pie bars. I know my friends will just love them.
High Altitude Tested. I develop all the recipes on my site for Denver’s altitude of 5,280 feet. If you’re at a lower or higher elevation, please see my FAQs for guidance on adjusting recipes for your altitude.
See the recipe card at the end of the post for the full ingredients list and instructions.
Ingredients
Cookie Bars
- Butter. The butter adds moisture and fat for a gooey, chewy texture. I use unsalted butter so I can control the saltiness of the oatmeal bars. And by browning the butter first, you’ll get an incredibly rich, nutty flavor from the butter that’s just incredible.
- Sugar. A combination of granulated sugar and brown sugar adds sweetness and moisture, as well as helps to caramelize the edges a beautiful golden brown color with a crisp texture.
- Eggs. Add structure and moisture, as well as help the bars puff up as they bake.
- Molasses. Adds more depth of flavor and a chewy texture. Use “light” old fashioned molasses, golden syrup or light treacle, not blackstrap molasses.
- Vanilla Extract. Flavor.
- All Purpose Flour. Binds the dough together and gives it structure.
- Oats. Adds a crunchy, chewy texture and wholesome flavor. I use old-fashioned rolled oats for all of my recipes.
- Spices. Cinnamon and ginger adds flavor and warmth.
- Baking Powder. Leavening agent so the bars puff up as they bake.
- Salt. Balances the sweetness.
Icing
- Powdered Sugar. Sweetens and thickens the icing.
- Meringue Powder. Helps to set the icing quickly.
- Vanilla Bean Paste. Adds rich vanilla flavor and pretty black specks.
- Ginger. A pinch of ground ginger in the icing and chopped caramelized ginger sprinkled on top adds heat and spice to balance the sweetness.
- Milk. Thins the icing to a drizzly consistency.
Instructions
Cookie Bars
- Preheat the oven to 350 F, and position a rack in the center of the oven. Lightly spray an 8 or 9 inch square baking pan with non-stick baking spray, or line the pan with parchment paper.
- In a saucepan, melt the butter over medium heat. Continue to cook the butter, swirling occasionally, until the water evaporates, the butter starts to foam and it forms fragrant, nutty, golden brown solids at the bottom of the pan. Remove from the heat and immediately pour the hot butter into a bowl, scraping all the golden browned bits off the bottom of the saucepan with a spatula.
- Add the granulated sugar and brown sugar to the hot browned butter and whisk for 1 minute. Then add the eggs, molasses and vanilla, and whisk for one minute.
- In a separate bowl, combine the flour, oats, cinnamon, ginger, baking powder and salt, until evenly distributed. Add the dry ingredients to the wet, and use a spatula to stir into a thick batter, just until the flour is incorporated.
- Spread the batter evenly into a prepared pan. Bake the bars for about 35 minutes (for an 8 inch pan) and 30 minutes (for a 9 inch pan). The bars will be slightly puffed and a deep golden brown color.
- As the cookie bars cool, it’s normal for the center of the bars to settle and sink back down while the edges stay raised. So while the bars are hot, I like to gently press the edges down with the bottom of a spatula, so that the bars are an even thickness all the way across as they cool.
- Set the pan on a cooling rack to cool for about an hour, before adding the icing.
Icing
- Stir together the powdered sugar, meringue powder, ground ginger, vanilla bean paste and milk until smooth and drizzly. Spread the icing in a thin, even layer over the cookie bars. Before the icing sets and crusts over, sprinkle the chopped candied ginger on top.
- Let cool for at least 1-2 more hours, until the bars are cooled and the icing is set, before cutting into squares.
Be sure to read all of my BAKING FAQs where I discuss ingredients, substitutions and common baking questions, so that you can be successful in your own baking!
Frequently Asked Questions
How should I store oatmeal cream pie bars?
Store the cooled, leftover bars in an airtight container at room temperature for up to 3 days.
Can these bars be frozen?
If you want to make the bars in advance, let them cool, then wrap them tightly in plastic wrap (without the icing). Freeze for up to 3-6 months. Let thaw at room temperature, then add the icing and let the icing set.
How can I make a double batch?
For a larger batch, double the recipe, and bake the bars in a 9×13 inch baking pan for 38 minutes.
What if I want to frost the bars with buttercream instead of the icing?
For a fluffy vanilla buttercream, I’d recommend my perfect American buttercream recipe.
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High Altitude Oatmeal Cream Pie Cookie Bars
All recipes on Curly Girl Kitchen are developed for high altitude at 5,280 feet. See FAQs for adjusting to higher or lower elevations.
Equipment
Ingredients
Cookie Bars
- 1 cup unsalted butter
- ⅔ cup granulated sugar
- ⅔ cup light brown sugar, lightly packed
- 2 large eggs
- 2 tsp light "original" molasses
- 1 tbsp vanilla extract
- 1 ½ cups all-purpose flour, fluffed, spooned and leveled
- 1 cup old fashioned rolled oats
- 1 ½ tsp ground cinnamon
- ¼ tsp ground ginger
- 1 ¼ tsp baking powder
- 1 tsp coarse Kosher salt (if using table salt, use half the amount)
Icing
- 1 cup powdered sugar
- 1 tbsp meringue powder (optional)
- 1 tsp vanilla bean paste (or vanilla extract)
- ⅛ tsp ground ginger
- 1 ½ – 2 tbsp whole milk
- 1 tbsp finely chopped candied ginger
Instructions
Cookie Bars
- Preheat the oven to 350 F, and position a rack in the center of the oven. Lightly spray an 8 or 9 inch square baking pan with non-stick baking spray, or line the pan with parchment paper.
- In a saucepan, melt the butter over medium heat. Continue to cook the butter, swirling occasionally, until the water evaporates, the butter starts to foam and it forms fragrant, nutty, golden brown solids at the bottom of the pan. Remove from the heat and immediately pour the hot butter into a bowl, scraping all the golden browned bits off the bottom of the saucepan with a spatula.
- Add the granulated sugar and brown sugar to the hot browned butter and whisk for 1 minute. Then add the eggs, molasses and vanilla, and whisk for one minute.
- In a separate bowl, combine the flour, oats, cinnamon, ginger, baking powder and salt, until evenly distributed. Add the dry ingredients to the wet, and use a spatula to stir into a thick batter, just until the flour is incorporated.
- Spread the batter evenly into a prepared pan. Bake the bars for about 35 minutes (for an 8 inch pan) and 30 minutes (for a 9 inch pan). The bars will be slightly puffed and a deep golden brown color.
- As the cookie bars cool, it's normal for the center of the bars to settle and sink back down while the edges stay raised. So while the bars are hot, I like to gently press the edges down with the bottom of a spatula, so that the bars are an even thickness all the way across as they cool.
- Set the pan on a cooling rack to cool for about an hour, before adding the icing.
Icing
- Stir together the powdered sugar, meringue powder, ground ginger, vanilla bean paste and milk until smooth and drizzly. Spread the icing in a thin, even layer over the cookie bars. Before the icing sets and crusts over, sprinkle the chopped candied ginger on top.Baker's Note: This makes a thin layer of icing, so as not to make the bars excessively sweet. For a thicker, more opaque layer of icing on top, increase the icing by 1 1/2 x.
- Let cool for at least 1-2 more hours, until the bars are cooled and the icing is set, before cutting into squares.
I made these today … will cut in a bit … They smell divine. I think the icing recipe might need to yield a bit more … I used the 2tbsp of milk … yet I do have some thinly covered spots here and there. Thanks for sharing. I’m at 6,300ft.
It’s definitely a thin layer of icing, so as not to make the bars excessively sweet. Thanks for the feedback, though, I’ll update that with a note in the recipe card, in case bakers want to increase the yield a little more.
If I only have dark molasses, will that work?
Since it’s such a small amount of molasses, it’ll be fine, and will just add a slightly deeper molasses flavor.
Thank you!
Does anyone know if it is ok to freeze with icing? The timing doesn’t work out for me to freeze then make icing later. Thank you!!
There may be some condensation on the icing after freezing and thawing, which could affect the appearance/texture of the icing, which would be my only concern. Taste-wise, they’ll be fine.
Thank you!
Fantastic!
Thank you for your dedication to the are of baking 🙂
My soon to be daughter in law wanted a country engagement party and these are her “cake”
A tip for people who like shapes, I’ve used springform pans to make several rounds of different sizes.
Doubling the recipe was perfect for 1-9” and 1-6” round.
Surrounded by small bouquets ox Gerber daisies and your oatmeal bar recipe was the star!
I’m at sea level 😉
One additional note, I topped it with blueberries ( a mound in the center).
It was a beautiful center for the dinner. Thank you so much for your recipe!!