Rhubarb cookies are an idea that sounds strange until you taste one, and then they make complete sense. The concept is close to an oatmeal raisin cookie: butter, brown sugar, eggs, oats, a little cinnamon. But instead of raisins, finely diced fresh rhubarb goes into the dough, bringing tartness and a little moisture that keeps the cookies from drying out. Cream cheese frosting on top makes them something closer to a bar than a plain drop cookie, and the tangy frosting against the slightly tart rhubarb crumb is the combination worth making these for.
This makes a large batch, forty-eight cookies, which is ideal for a bake sale, a gathering, or simply having cookies around for the week. The rhubarb season is short and this is one of the better things you can do with it while it lasts.
What rhubarb does in a cookie
Rhubarb is a vegetable treated as a fruit, which means it’s high in water content and very tart. In a pie it needs a lot of sugar to compensate. In a cookie dough, the tartness is still there but it’s balanced by the brown sugar base without needing extra compensation. The rhubarb softens in the oven and almost disappears into the crumb, leaving behind pockets of slight tartness and extra moisture.
Finely dicing the rhubarb is important. Large pieces release too much water in one spot and can make the surrounding cookie dough gummy. Quarter-inch pieces or smaller distribute evenly and give you rhubarb in most bites without any wet patches. If you’re starting with frozen rhubarb, thaw it completely and squeeze out excess moisture with a kitchen towel before dicing. Frozen rhubarb carries a lot of water and if it goes in undrained it will make the dough too wet to hold shape on the baking sheet.
The dough
Beat the softened butter and brown sugar together until creamy, a full minute or two in a stand mixer or with a handheld mixer. The creaming step adds air and starts building the cookie’s structure. Add the eggs and vanilla and beat well. The combined dry ingredients, flour, baking soda, cinnamon, and salt, go in next and get mixed just until incorporated. Then the oats and diced rhubarb, stirred in by hand or on low speed.
Quick-cooking oats rather than rolled oats. Quick oats are thinner and softer and give the cookie a more even texture. Rolled oats are chewier and stay more distinct in the baked cookie, which some people prefer. Either works; the texture differs more than the flavor.
The dough will look slightly wetter than a standard oatmeal cookie dough because of the rhubarb. That’s normal. Drop by rounded tablespoons onto ungreased baking sheets with space between each one since they spread slightly.
The bake and what to watch for
350 degrees for fifteen to eighteen minutes. The instruction to not overbake is real and worth following: these cookies should come out of the oven when they still look almost set in the center, not fully firm. They continue cooking on the hot pan for the first minute after you pull them, and they firm up further as they cool. An overbaked rhubarb cookie is dry; a slightly underbaked one is soft and tender when it cools.
One minute on the baking sheet, then to a wire rack to cool completely before frosting. Frosting warm cookies is a waste of good cream cheese frosting; it slides and melts and the results look messy. Full cool is twenty to thirty minutes, and the cookies are better for the wait.
The cream cheese frosting
Four ounces of softened cream cheese and four tablespoons of softened butter, beaten together until smooth and combined. Add two cups of powdered sugar and a teaspoon of vanilla and beat until the frosting is fluffy and smooth. If it’s too thick to spread, add milk a teaspoon at a time until it reaches a spreadable consistency. It shouldn’t be runny; it should sit on the cookie rather than sliding off.
Spread a rounded teaspoon of frosting on each cooled cookie. You can pipe it for a neater look or just use a small offset spatula or the back of a spoon. The frosting is soft enough to spread easily and sets slightly as it sits, which makes the cookies easier to stack.
Rhubarb and the short window for baking with it
I think about rhubarb the way I think about a handful of other seasonal ingredients: there’s a window of a few weeks where it’s everywhere and cheap, and then it’s gone. In Morocco where I grew up, the equivalent was certain citrus and figs and early tomatoes. You learned to make things with them when they were there, because waiting meant missing the season entirely.
Rhubarb cookies aren’t a common recipe in most of the places I’ve cooked, and that makes them interesting to me. They use an ingredient that most people know only from pie and they turn it into something familiar, a soft, frosted drop cookie, with a character that’s distinctly its own. Makes 48 cookies. Store covered at room temperature for two to three days, or refrigerate if the frosting feels too soft in warm weather.
Storing and freezing
Unfrosted cookies freeze well for up to three months. Freeze them flat on a baking sheet until solid, then transfer to a bag. Thaw at room temperature and frost when ready to serve. Frosted cookies can be refrigerated for up to four days but the frosting can absorb moisture and become soft; keep them covered and bring to room temperature before serving.
Frosted Rhubarb Cookies with Cream Cheese Frosting
Description
Soft oatmeal drop cookies with finely diced rhubarb for tartness and moisture, topped with a tangy cream cheese frosting. Makes 48 cookies.
Ingredients
Instructions
-
Preheat the oven to 350 degrees Fahrenheit.
-
Beat the butter and brown sugar together until creamy, about 1 to 2 minutes. Add the eggs and vanilla and beat well.
-
Add the flour, baking soda, cinnamon, and salt to the bowl and mix until just combined.
-
Stir in the oats and finely diced rhubarb until evenly distributed.
-
Drop rounded tablespoons of dough onto ungreased baking sheets, spaced about 2 inches apart. Bake for 15 to 18 minutes until almost set. Do not overbake.
-
Cool 1 minute on the baking sheet, then transfer to a wire rack. Cool completely before frosting.
-
Make the frosting: beat the cream cheese and butter together until smooth. Add the powdered sugar and vanilla and beat until fluffy. Add milk a teaspoon at a time if needed for a spreadable consistency.
-
Spread a rounded teaspoon of frosting onto each cooled cookie. Store covered..
Nutrition Facts
Servings 48
- Amount Per Serving
- Calories 115kcal
- % Daily Value *
- Total Fat 1g2%
- Total Carbohydrate 21g8%
- Dietary Fiber 2g8%
- Protein 6g12%
* Percent Daily Values are based on a 2,000 calorie diet. Your daily value may be higher or lower depending on your calorie needs.
Note
These figures appear inconsistent with the butter and brown sugar quantities in the recipe and may be inaccurate. Finely dice the rhubarb to avoid wet pockets in the dough. If using frozen rhubarb, thaw and squeeze dry before using.
