Rhubarb Oatmeal Bar sitting on marble top with pink vintage plate and fork in the background.
Print Recipe Add to Collection
4.13 from 8 votes

Rhubarb Oatmeal Bars

This recipe for rhubarb oatmeal bars from my Grandma’s recipe box carries with it memories of an avocado green oven, matchbox cars and a grandpa I never met.
Prep Time20 mins
Cook Time25 mins
Total Time45 mins
Course: Dessert, Dessert Bars
Cuisine: American
Servings: 24 bars
Calories: 208kcal



  • 3 cup chopped rhubarb
  • 1 1/2 cup sugar
  • 2 1/2 tablespoons cornstarch , dissolved in 1/4 cup water
  • 1 teaspoon vanilla


  • 1 1/2 cup oatmeal
  • 1 1/2 cup flour
  • 1 cup brown sugar
  • 1/2 cup chopped walnuts
  • 1/2 teaspoon soda
  • 1 cup butter , melted


  • Heat oven to 375˚ F.
  • To make filling, in a medium sauce pan over medium-high heat combine rhubarb, sugar, cornstarch mixture and vanilla.
  • Heat until rhubarb is tender and mixture is thickened. Remove from heat and set aside.
  • To make crumble, in a large mixing bowl combine oatmeal, flour, sugar, soda and nuts. Pour melted butter over and mix until crumbly.
  • To assemble, press 3/4 of the crumble mixture into the bottom of a 9 x 13 baking pan.
  • Pour the rhubarb mixture over. Sprinkle the remaining crumble over the top
  • Bake until filling is bubbly and topping is golden brown, about 20 - 25 minutes.
  • Serve with whipped cream or vanilla ice cream.


Serving: 12bars | Calories: 208kcal | Carbohydrates: 29.6g | Protein: 2.3g | Fat: 9.6g | Saturated Fat: 5g | Cholesterol: 20mg | Sodium: 85mg | Potassium: 95mg | Fiber: 1.2g | Sugar: 18.7g | Calcium: 20mg | Iron: 0.7mg