featured 150064

Brown Sugar Oatmeal Cookies with Tangy Rhubarb

If you love rhubarb, you’ll enjoy these Oatmeal Brown Sugar Rhubarb Cookies. They are simple drop cookies made with oats and chopped rhubarb, flavored with cinnamon and a touch of orange zest. This recipe works with fresh or frozen rhubarb and makes a tasty variation on classic oatmeal cookies.

rhubarb oatmeal cookie, broken in half, on a piece of parchment paper

Rhubarb is at its best in spring, and these cookies are a great way to showcase its bright, tart flavor. The recipe was adapted from a straightforward oatmeal cookie base and pairs well with coffee, tea, or a glass of milk. Use the ingredients and steps below to bake a batch of chewy, slightly tangy cookies studded with pink rhubarb pieces.

Rhubarb behaves like a fruit in baking and adds a lovely tart contrast to the sweetness of brown sugar and oats. If you enjoy experimenting with rhubarb, try it in crisps, squares, muffins, or coffee cake for other great results.

rhubarb square on a white plate, with glass dish of more rhubarb squares in the background

Ingredients

You’ll need the following to make Oatmeal Brown Sugar Rhubarb Cookies:

rhubarb cookie ingredients in glass bowls, labelled
  • ½ cup unsalted butter
  • ½ cup white sugar
  • ½ cup brown sugar
  • 1 tsp cinnamon
  • 1 tsp orange zest
  • 1 tsp vanilla extract
  • 1 large egg
  • 2 cups all-purpose flour (start with 1¾ cups if using fresh rhubarb and add more as needed)
  • ½ tsp baking soda
  • 1¾ cups quick-cooking rolled oats
  • 1–1½ cups chopped rhubarb (measure after defrosting if using frozen)

Instructions

Prep: Preheat the oven to 350°F (175°C). Line a baking sheet with parchment paper or lightly spray with nonstick spray.

Chop fresh rhubarb into small pieces. If using frozen rhubarb, thaw and drain any excess liquid before measuring.

sugars, butter, egg and vanilla extract in a glass bowl

Combine the butter, white sugar, brown sugar, egg, and vanilla extract in a large bowl.

butter, sugars, egg and vanilla beaten together in glass bowl with beaters over top

Beat with an electric mixer on medium speed until the mixture is light and fluffy.

flour, cinnamon and baking soda mixed together in medium glass bowl

Whisk together the flour, cinnamon, and baking soda in a separate bowl.

dry ingredients mixed together with butter mixture

Add the dry ingredients to the butter mixture and beat until just combined.

remaining ingredients added to the glass bowl

Stir in the rolled oats, chopped rhubarb, and orange zest with a wooden spoon or spatula until evenly distributed.

rhubarb cookie dough in a glass bowl with a dark brown wooden spoon

The mixture should come together into cookie dough. If the dough seems too wet (more likely with fresh rhubarb), add a little more flour until the texture is right.

Form Cookies: Drop heaping tablespoonfuls of dough onto the prepared baking sheet, or use a medium cookie scoop for uniform cookies.

cookie dough in heaping tablespoons on a parchment lined baking sheet

Bake in the preheated oven for about 18 minutes, or until the bottoms are lightly golden brown.

baked cookies on parchment covered baking sheet

Remove from the oven and cool on the baking sheet for about 3 minutes, then transfer to a wire rack to cool for an additional 3–5 minutes or until set.

hand holding up lightly browned on bottom rhubarb cookie

If you like, garnish with additional grated orange zest before serving for a bright finishing touch.

rhubarb cookies on a wire cooking rack, with a turquoise spatula and a flowered tea towel under the rack

Variations & Substitutions

  • Butter: Salted butter can be used; you may want to add a tablespoon or two more sugar if preferred.
  • Rhubarb: Fresh or frozen work fine. If using frozen, thaw and drain before measuring.
  • Oats: Quick oats are recommended for a softer texture. If using old-fashioned oats, pulse them briefly in a food processor for a similar texture, or leave them whole for a chewier cookie.
  • Zest: Swap orange zest for lemon zest if you prefer a different citrus note.
rhubarb cookie being dipped into a black mug of coffee

Equipment

Basic equipment for this recipe includes an electric mixer (hand or stand), a large mixing bowl, a medium bowl for dry ingredients, a wooden spoon or spatula, a baking sheet, and a cooling rack. A cookie scoop makes portioning easier.

Storage

Store cookies in an airtight container at room temperature for up to 3 days. For longer storage, freeze in a sealed container or freezer bag for up to 3 months.

Serving Size

This recipe yields about 30 cookies. You can scale the recipe up or down to suit your needs.

rhubarb cookie broken in half on a piece of parchment with more cookies and rhubarb in the background

Food Safety

  • Do not use the same utensils for cooked food that touched raw egg.
  • Wash hands after handling raw egg.
  • Do not eat raw cookie dough.
  • Do not leave food at room temperature for extended periods.
  • Keep good ventilation when cooking on gas and never leave cooking food unattended.

Frequently Asked Questions

Can I use frozen rhubarb in my cookie recipe?

Yes. Thaw the rhubarb, drain off excess liquid, and measure it after draining so the dough doesn’t become too wet.

Comments & Reviews

If you try this recipe and enjoy it, leaving a comment or rating is a great way to support the recipe creator.

Whether you have fresh stalks or frozen rhubarb, these cookies highlight the vegetable’s tartness alongside oats and warm spices for an easy, satisfying treat.