Oatmeal Cookie Sweet Potato Casserole

This Oatmeal Cookie Sweet Potato Casserole has all the Fall flavors in a one-pan dish including cranberries, raisins, cinnamon, pecans and sweet potato.  It’s the perfect sweet side dish to accompany all those savory Thanksgiving dishes!

Oatmeal Cookie Sweet Potato Casserole

This Sweet Potato Casserole is the dish that everyone is going to look forward to because it’s like having a dessert during dinner!  It has a classic sweet potato casserole, with a layer of marshmallows and then topped with oatmeal raisin cranberry cookie crust!

This recipe is partly inspired by my Oatmeal Raisin Cranberry Cookies recipe.  I added 1/4 cup chopped pecans which goes perfectly with the oatmeal cookie crust and sweet potato.  If you prefer, you can substitute the same amount in walnuts or skip the nuts altogether.  I found that the addition of pecans added a nice, subtle, nutty crunch to the casserole.

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Ingredients for Oatmeal Cookie Sweet Potato Casserole

Oatmeal Raisin Cranberry Cookie and Marshmallow Topping

• ½ cup (1 stick) PLUS 6 tablespoons butter, softened, I prefer really soft, room temperature butter
• ¾ cup brown sugar
• ½ cup granulated sugar
• 2 large eggs
• 1 teaspoon vanilla
• 1-1/2 cups all-purpose flour
• 1 teaspoon baking soda
• 1 teaspoon ground cinnamon
• ½ teaspoon kosher salt
• 3 cups old-fashioned whole oats
• 1/2 cup dried cranberries
• 1/4 cup pecans, chopped
• 1 (10 ounce) bag mini-marshmallows (if you only have regular-size marshmallows on hand, cut them down to mini-marshmallow size)

Sweet Potato Casserole Filling

• 5 cups (about 6 large) cooked sweet potatoes
• butter for greasing 13” x 9” x 2” oven-safe baking pan
• 2 large eggs
• 1 teaspoon vanilla extract
• ½ milk (can substitute cream or half and half)
• 4 tablespoons (½ stick) butter
• Optional: up to 1 cup of sugar *depending on sweetness of sweet potatoes, if the sweet potatoes are really sweet, then I usually skip the sugar.

Tips for Success for Oatmeal Cookie Sweet Potato Casserole

1. To save time, you can make the oatmeal cookie topping and the mashed sweet potatoes ahead of time the day before.
2. When you are baking the sweet potatoes you can just bake them on the wire rack or on a foil-lined baking sheet if you don’t want any drips in the oven. Make sure you wash and stab the sweet potatoes with a fork before baking.
3. The baking time can really vary for the sweet potatoes because the varying size of sweet potatoes.  I usually set the timer for 1 hour (at 350 degrees F) and poke a fork in them to test.  The fork should go in and come out easily and if there’s any resistance they need more time.  You might have some smaller ones that are done and larger ones that need more time, so just leave the ones that need more time in and check periodically until fully cooked.
4. Make sure you measure the 5 cups of sweet potatoes and the other ingredients exactly because you will need the entire volume of the pan for this recipe.  You can bake the casserole over a cookie sheet if you are concerned about drips.
5. The casserole’s total baking time is 40 minutes but it’s possible that it will be done at 30 minutes depending on preference.  I add an extra 10 minutes, with an optional foil tent to get a really crispy oatmeal cookie crust you you might prefer something different.  Make sure all the ingredients at every layer are evenly distributed to ensure even baking.

Kitchen Tools Needed for Oatmeal Cookie Sweet Potato Casserole

1. 13″ x 9″ x 2″ oven safe baking pan or better a 13″ x 9″ x 3″ baking pan – I have a 13″ x 9″ x 2″ pan and with all the ingredients it does get a little overfilled above the upper edge but as long as all the ingredients have been measured properly and evenly spread, everything should fit.  You can always put a cookie sheet under the baking pan if you are concerned about drips.
2. Electric hand mixer or stand mixer – I used my hand mixer and that had sufficient power for mixing both the oatmeal cookie crust and the sweet potato casserole filling.
3. large mixing bowl
4. baking spatula

The aroma in your house is amazing while this Oatmeal Cookie Sweet Potato Casserole is baking in the oven :)

I hope you enjoy this sweet and delicious casserole as much as my family and I do!  Enjoy!

MORE SIDE DISHES YOU MIGHT LIKE:

1. Potatoes Au Gratin have been a favorite in many households. Add bacon and leeks and you have a delicious side dish that everyone will love!
2. Speaking of potatoes, these potatoes are roasted in a cast iron skillet in a savory broth that makes them irresistible.
3. We usually only think of stuffing, some call it dressing, at Thanksgiving. But really it can be enjoyed with poultry any time of year. Try my stuffing with parsley, sage, rosemary & thyme (anyone remember the song?) next time you make it.
4. If you’re looking to add some southwestern flair to your dinner, this Spanish rice with black beans and corn is a great side dish.

And for using up more sweet potatoes, check out these Sweet Potato Oat Cookies! These “healthier” cookies are perfect for holiday cookie exchanges and are great for enjoying a delicious chocolatey treat without as much guilt.

Oatmeal Cookie Sweet Potato Casserole

This Oatmeal Cookie Sweet Potato Casserole has all the Fall flavors in a one-pan dish including cranberries, raisins, cinnamon, pecans and sweet potato. It’s the perfect sweet side to accompany all those savory Thanksgiving dishes!

5 from 1 vote

IMPORTANT - There are often Frequently Asked Questions within the blog post that you may find helpful. Simply scroll back up to read them!

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Course: Sides

Cuisine: American

1 hour hr 50 minutes mins

Author: Amanda Davis

Ingredients

• ▢ Oatmeal Raisin Cranberry Cookie and Marshmallow Topping:
• ▢ ½ cup 1 stick PLUS 6 tablespoons butter, softened, I prefer really soft, room temperature butter
• ▢ ¾ cup brown sugar
• ▢ ½ cup granulated sugar
• ▢ 2 large eggs
• ▢ 1 teaspoon vanilla
• ▢ 1-1/2 cups all-purpose flour
• ▢ 1 teaspoon baking soda
• ▢ 1 teaspoon ground cinnamon
• ▢ ½ teaspoon kosher salt
• ▢ 3 cups old-fashioned whole oats
• ▢ ½ cup dried cranberries
• ▢ ¼ cup pecans chopped
• ▢ 1 10 ounce bag mini marshmallows
• ▢ Sweet Potato Filling:
• ▢ 5 cups about 5-6 large cooked sweet potatoes, mashed
• ▢ butter for greasing 13” x 9” x 2” oven-safe baking pan
• ▢ 2 large eggs
• ▢ 1 teaspoon vanilla extract
• ▢ ½ cup milk can substitute cream or half and half
• ▢ 4 tablespoons ½ stick butter
• ▢ Optional: up to 1 cup of sugar *depending on sweetness of sweet potatoes you can taste test the sweet potatoes after they are baked and cooled

Before You Begin

To save time, you can make the oatmeal cookie topping and the mashed sweet potatoes ahead of time the day before.
When you are baking the sweet potatoes you can just bake them on the wire rack or on a foil-lined baking sheet if you don’t want any drips in the oven. Make sure you wash and stab the sweet potatoes with a fork before baking.
The baking time can really vary for the sweet potatoes because the varying size of sweet potatoes. I usually set the timer for 1 hour (at 350 degrees F) and poke a fork in them to test. The fork should go in and come out easily and if there's any resistance they need more time. You might have some smaller ones that are done and larger ones that need more time, so just leave the ones that need more time in and check periodically until fully cooked.
Make sure you measure the 5 cups of sweet potatoes and the other ingredients exactly because you will need the entire volume of the pan for this recipe. You can bake the casserole over a cookie sheet if you are concerned about drips.
The casserole's total baking time is 40 minutes but it's possible that it will be done at 30 minutes depending on preference. I add an extra 10 minutes, with an optional foil tent to get a really crispy oatmeal cookie crust you you might prefer something different. Make sure all the ingredients at every layer are evenly distributed to ensure even baking.

Instructions

• Preheat oven to 350 degrees. Bake sweet potatoes for 1 hour or until cooked and tender. When they are done, allow them to cool completely.
• Grease a 13” x 9” x 2” oven-safe baking pan, set aside.
• Oatmeal Cookie & Marshmallow Topping:
• Note: All the ingredients, including the eggs, should be at room temperature before starting the oatmeal cookie topping. In a large mixing bowl, beat the softened butter, brown sugar, granulated sugar on medium speed until creamy. In a small mixing bowl, combine flour, baking soda, cinnamon and salt and mix well. Add combined dry ingredients incrementally to creamed butter mixture, mix well. Add 2 eggs and vanilla and mix well. Add oats, cranberries, raisins and chopped pecans, mix well.
• Peel cooled sweet potatoes and measure exactly 5 cups mashed sweet potatoes. In a large mixing bowl, mix mashed sweet potatoes, 2 eggs, 1/2 cup milk, 4 tablespoons butter, 1 teaspoon vanilla, and sugar (optional depending on taste preference). Spread sweet potato mixture evenly in the greased 13" x 9" x 2" baking pan. Add mini-marshmallows in an even layer on top, press them down. Add oatmeal cookie dough in an even layer on top of the marshmallows. Alternately, you can reserve half of the mini-marshmallows to have on top of the cookie layer. Bake for 30 minutes at 350 degrees F on the middle rack. At 30 minutes check on the casserole and if you are concerned about the top browning too much, add a foil tent over the top. Bake for 10 minutes more for a total time of 40 mins. When the casserole is done, allow to cool for at least 10 minutes before serving. Enjoy!

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Recipe Attribution

This recipe is partly inspired by Add a Pinch and Oatmeal Raisin Cranberry Cookies by Life’s Little Sweets