The BEST Chewy Rhubarb Oatmeal Cookies (with Lemon Glaze)

Name: Rhubarb Oatmeal Cookies (with Lemon Glaze)
Prep time: 15 min
Cook time: 12 min
Total time: 57 min
Ingredients: 1 cup unsalted butter (room temperature); 0.75 cup brown sugar; 0.5 cup granulated sugar; 2 eggs (large); 2 tsp vanilla extract; 1.5 cups all-purpose flour; 1 tsp baking soda; 0.5 tsp salt; 1 tsp cinnamon (optional); 2 cups quick oats; 1.5 cups rhubarb (finely diced); 0.75 cup powdered sugar; 1 tbsp lemon juice (fresh); 0.5 tsp lemon zest

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Ready to upgrade your spring baking? This rhubarb cookies recipe brings together chewy oats, tangy diced rhubarb, and a bright lemon glaze to create a soft-baked cookie with serious personality. Unlike most plain rhubarb cookies, this recipe adds texture, depth, and flavor balance in every bite. I’ll walk you through each step—from how to prep rhubarb properly to why the glaze turns these from good to unforgettable. This isn’t just another cookie—it’s the rhubarb cookies recipe you’ll crave all season long.

How I Found the Perfect Rhubarb Cookies Recipe (After a Few Fails)

Oatmeal, Meet Rhubarb

I’m Ava, and if you know my baking style, you know I love a twist on a classic. My cookie jar’s seen everything from hot Cheeto shortbread (yep, I went there) to peanut butter miso. But nothing surprised me more than how good rhubarb is in a cookie—once I figured out how to do it right.

The first rhubarb cookies recipe I tried was a soggy mess. Big chunks of rhubarb bled moisture into the dough, turning everything cakey. It lacked the chew I love in oatmeal cookies. But that failure got me obsessed. What if I took my favorite oatmeal cookie base, folded in finely chopped rhubarb, and added a lemon glaze to tie it all together?

That’s how this chewy, tart-sweet, perfectly glazed rhubarb oatmeal cookies recipe was born.

Why This Rhubarb Cookies Recipe Works

Unlike the top-ranking versions online, this cookie doesn’t rely on just brown sugar or butter to carry the flavor. Instead, I’ve built it for texture and balance. The oatmeal makes each bite hearty and soft, the lemon glaze brightens the earthy notes, and the rhubarb… well, it finally shines.

Plus, this rhubarb cookies recipe is easy. You don’t need fancy tools or complicated steps. Just good ingredients, a chill step that prevents spreading, and a quick glaze that sets into a shiny finish.

Rhubarb Oatmeal Cookies (with Lemon Glaze)

Ava Thompson

These soft and chewy rhubarb oatmeal cookies combine tart rhubarb with hearty oats and a sweet lemon glaze for the perfect spring bake.

5 from 1 vote

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Prep Time 15

Cook Time 12

Total Time 57

Course Dessert

Cuisine American

Servings 24 cookies

Calories 150 kcal

Equipment

Mixing Bowls
Baking sheet
Parchment paper
Wire Rack
Hand mixer

Ingredients

Cookie Dough

1 cup unsalted butter room temperature
0.75 cup brown sugar
0.5 cup granulated sugar
2 eggs large
2 tsp vanilla extract
1.5 cups all-purpose flour
1 tsp baking soda
0.5 tsp salt
1 tsp cinnamon optional
2 cups quick oats
1.5 cups rhubarb finely diced

Lemon Glaze

0.75 cup powdered sugar
1 tbsp lemon juice fresh
0.5 tsp lemon zest

Instructions

Cream the butter, brown sugar, and granulated sugar until light and fluffy.
Add eggs and vanilla extract, and mix until just combined.
In a separate bowl, whisk together the flour, baking soda, salt, and cinnamon. Stir in oats.
Fold the dry ingredients into the wet mixture until just combined.
Gently fold in the finely diced rhubarb. Do not overmix.
Cover and chill the dough for 30–60 minutes.
Preheat oven to 350°F (175°C). Line baking sheets with parchment paper.
Scoop dough into 2-tablespoon-sized balls and place 2 inches apart.
Bake for 10–12 minutes, until edges are golden and centers are just set.
Cool for 5 minutes on the sheet, then transfer to a wire rack to cool completely.
Mix powdered sugar, lemon juice, and zest until smooth to form glaze.
Drizzle glaze over cooled cookies and let it set before serving.

Notes

Optional: Add 1/2 cup white chocolate chips or chopped walnuts. Dough freezes well. Glaze can be refrigerated up to 3 days.

Keyword lemon glaze, oatmeal cookies, rhubarb cookies recipe

The Ingredients Behind the Magic

Choosing the Right Ingredients for Rhubarb Oatmeal Cookies

This rhubarb cookies recipe starts with a soft oatmeal cookie base—nothing complicated, just smart choices. We use quick oats (not rolled or steel-cut), which give the cookies a chewy center without making them too dense. All-purpose flour adds just enough structure, while brown sugar brings moisture and a hint of molasses flavor that plays well with tart rhubarb.

Here’s what you’ll need:

Fresh rhubarb: Finely diced, about ¼-inch. You want it small enough to melt into the dough without making it soggy.
Quick oats: For chew and balance. Don’t substitute rolled oats—they’ll make the texture too coarse.
Brown + granulated sugar: Brown sugar for softness; white sugar for crisp edges.
Lemon zest + juice: These show up in the glaze and give this rhubarb cookies recipe a fresh, bright finish.
Egg, butter, vanilla: The usual cookie suspects—just make sure your butter is room temp for creaming.
Baking soda + salt: For lift and balance.

Optional upgrades:

Add white chocolate chips for creaminess.
Sub a teaspoon of cardamom for cozy spice.
Sprinkle raw sugar on top before baking for sparkle and crunch.

ingredients for rhubarb cookies recipe — Simple pantry ingredients plus fresh rhubarb

Rhubarb Prep: Do This First

Rhubarb can be tricky—prep it wrong and your cookies turn watery or brown. Here’s what works:

Wash and dry thoroughly.
Trim ends, then slice lengthwise if stalks are thick.
Dice into ¼-inch cubes. Uniform pieces bake evenly.
Optional: Toss with ½ tsp sugar and let sit 10 minutes, then pat dry. This draws out excess moisture and prevents sogginess.

This rhubarb oatmeal cookies recipe depends on good prep—don’t skip this step. It’s how we get sweet-tart pops without the mess.

How to Make This Rhubarb Cookies Recipe Step by Step

Step-by-Step Baking Instructions

This rhubarb cookies recipe comes together in under an hour (plus chill time), and every step helps lock in texture and flavor.

🕒 Prep Time: 15 min
🧊 Chill Time: 30 min
🔥 Bake Time: 10–12 min
🍪 Yield: ~24 cookies

1. Cream the butter + sugars
In a large bowl, beat 1 cup room temp unsalted butter with ¾ cup brown sugar and ½ cup granulated sugar until light and fluffy—about 2 minutes. This builds structure and prevents flat cookies.

mixing cookie dough for rhubarb cookies — Creaming butter and sugar for the dough

2. Add wet ingredients
Mix in 2 eggs and 2 tsp vanilla extract until just combined.

3. Combine dry ingredients
In a separate bowl, whisk together:

1½ cups all-purpose flour
1 tsp baking soda
½ tsp salt
1 tsp cinnamon (optional)

4. Stir in oats
Add 2 cups quick oats to the dry mixture, then fold it into the wet ingredients.

5. Fold in rhubarb
Gently fold in 1½ cups finely diced rhubarb. Don’t overmix—overworking releases too much moisture. For extra depth, try adding ½ cup white chocolate chips or walnuts.

folding rhubarb into oatmeal cookie dough — Folding rhubarb into the cookie mix

6. Chill the dough
Cover and chill for 30–60 minutes. This prevents spreading and helps the oats hydrate fully—essential in any rhubarb oatmeal cookies recipe.

7. Bake
Scoop dough onto parchment-lined sheets, 2 inches apart. Bake at 350°F (175°C) for 10–12 minutes, until edges are golden and centers look just set. Let cool on pan for 5 minutes before transferring to a rack.

Final Touch: Lemon Glaze

Mix ¾ cup powdered sugar with 1 tbsp lemon juice + ½ tsp zest. Drizzle over cooled cookies for brightness that balances the tangy rhubarb beautifully.

serving rhubarb cookies with tea — Perfect for afternoon tea or dessert

How to Store, Tweak, and Master This Rhubarb Cookies Recipe

Storage + Make-Ahead Tips

Once you’ve baked a batch of this rhubarb cookies recipe, let them cool completely before storing.

Countertop: Store in an airtight container for up to 3 days. Add a slice of bread to keep them soft.
Fridge: Fine for up to 6 days, but may firm up—reheat briefly for that fresh-baked texture.
Freezer: Freeze baked cookies (glazed or unglazed) for up to 2 months. You can also freeze dough balls—just bake straight from frozen and add 1–2 extra minutes.

This rhubarb oatmeal cookies recipe is a great make-ahead option. The dough actually improves in texture if chilled overnight.

Flavor Variations

Lemon cardamom glaze: Swap cinnamon for cardamom and use lemon glaze on top.
White chocolate twist: Add ½ cup white chocolate chips.
Vegan version: Use plant butter + flax eggs (1 tbsp ground flax + 3 tbsp water = 1 egg).
Strawberry rhubarb: Replace ½ the rhubarb with finely chopped fresh strawberries.

FAQ: Troubleshooting Your Rhubarb Cookies Recipe

1. My cookies spread out and were too cakey. What went wrong with my rhubarb cookies recipe?

This is a very common issue, but it’s easy to fix! The two main causes are not chilling the dough long enough (which is a critical step) or overmixing the batter after adding the rhubarb. For this recipe to have the perfect chewy texture, be sure to chill the dough for at least 30 minutes and fold the rhubarb in very gently at the very end. Overworking the dough can cause the rhubarb to release too much water.

2. Can I use frozen rhubarb in this recipe?

Yes, absolutely, and it’s a great option when rhubarb isn’t in season. Do not thaw the rhubarb first. Thawing will make it watery and can ruin the cookie’s texture. Simply chop the rhubarb while it is still frozen and fold it directly into the dough. You may need to add 1-2 minutes to the total bake time.

3. How can I adapt this recipe to be gluten-free?

This recipe adapts beautifully for a gluten-free diet. Use a high-quality 1-to-1 gluten-free baking flour (like Bob’s Red Mill or King Arthur) in place of the all-purpose flour. You also must ensure you use certified gluten-free quick oats. No other changes to the ingredients or instructions are necessary, and the final texture holds up exceptionally well.