These unconventional overnight oatmeal cookies will shatter your “good cookie” rules. They are full of balanced sweet flavor, but challenge the notion of textural perfection. They bake up very soft and just lightly chewy in the middle, like classic oatmeal cookies. But they lightly spread, creating a chewier sweet edge. This might seem like a flaw at first, but it’s an addictive bonus in my opinion. Not to mention, you’ll love how easy this flourless recipe is to make!
Mama’s Overnight Oatmeal Cookies are Fabulously Butterless and Flourless
This recipe was originally shared by Sarah – it’s one of her family favorites. But I made a little tweak to the recipe, added information, and expanded the directions with more detail. So it’s become a team effort! I also took some photos, and have answers to some common questions for these overnight oatmeal cookies.
Overnight Oatmeal Cookies FAQ
- Can You Use Rolled Oats? Stick with quick oats. They are just as nutritious, but are sliced thinner than rolled oats. This allows them to more readily soak up the oil and sugar, producing a more tender cookie.
- Do I Have to Leave the Oats Overnight? We recommend it. While sitting, the oats absorb much of the oil and sugar, to help make a more cohesive cookie when baked. If you want to bake in the evening, just stir together the oat mixture in the morning. You can even mix it up a whole day in advance. I’ve forgotten the oat mixture on my counter before – it’s fine!
- Should I Grease the Baking Sheets? No. Grease will cause these overnight oatmeal cookies to spread more. Using parchment paper instead helps to absorb some moisture so they spread, but not too much.
- Can I Substitute the Eggs? I don’t recommend it. Because this recipe is “flourless” and chunky, eggs are the primary binder. If you need egg-free oatmeal cookies, try my Allergy-Friendly Oatmeal Cookies (also gluten-free) or Hannah’s Bakery-Style Vegan Oatmeal Cookies.
- Is this a Good Recipe for Kids? It’s great for getting kids into baking! Even little kids can help with measuring, mixing (done by hand), and putting the dough on the baking sheets. Older kids and teens who use the oven, can make these on their own.
- Why is the Dough So Crumbly? This is a flourless recipe. Don’t worry, it binds together as it bakes! Just dampen your hands (it’s sticky!) and press any loose bits back into the mounds of dough before baking. You can alternatively press the dough into muffin cups (use a piece of parchment to press to prevent sticking) if you want more even cookies.
- Can I Add Cinnamon? By all means! If you like a little spice, add 1 to 2 teaspoons of cinnamon when you mix up the initial oat mixture. Another option is to add a couple teaspoons of pumpkin pie spice.
- Can I Add Chocolate Chips or Raisins? This gets a little trickier. Since the dough is quite crumbly to start, it can get more difficult to handle if you add more chunky items. Mini chocolate chips will work best, but instead, I recommend Sarah’s chocolate dip suggestion in the recipe notes.
Special Diet Notes: Overnight Oatmeal Cookies
By ingredients, this recipe is dairy-free / non-dairy, gluten-free, nut-free, peanut-free, soy-free, and vegetarian.
- 4 cups quick oats (use certified gluten-free oats, if needed)
- 1½ cups light brown sugar, packed
- 1 cup oil
- 2 eggs, beaten
- 1 teaspoon vanilla extract
- 1 teaspoon salt
- The night before you bake, thoroughly stir together the oats, brown sugar, and oil in a large bowl. They should start to come together like a clumpy dough.
- Cover the oat mixture and let sit at room temperature overnight (or longer if needed).
- The next day, when ready to bake, preheat your oven to 325ºF and line baking sheets with parchment paper.
- In a medium bowl, whisk together the eggs, vanilla, and salt until beaten and combined.
- Pour the egg mixture into your oat mixture and stir until combined.
- Drop the dough by the level tablespoonful onto your prepared baking sheets a few inches apart. This is a very loose, crumbly dough. If needed, wet your hands to shape the dough and press it together. But leave the dough as mounds - don't flatten them. The cookies do spread on the edges as they bake.
- Bake the cookies for 15 minutes.
- Let the cookies cool on the baking sheets for 2 minutes, before removing them to a wire rack to cool completely.
- Store the cookies in an airtight container at room temperature for a few days. Freeze the cookies for longer storage.