This recipe for Rhubarb Bars will get that last bag of rhubarb right out of the freezer. Pair it with another pantry staple, oatmeal and you’ve got cookies you make just about anytime. Got strawberries? Try my Strawberry Rhubarb Bars! I also have a recipe for  Blueberry Bars that we love too. And don’t forget you can make any of them with frozen fruit.

making cookie bars out of pantry staples

Rhubarb Bars

This is what you make when you open the freezer and a bag of frozen rhubarb falls out on your toe, and when that 10-pound box of oatmeal you bought at Costco seems more like 50 pounds. Using up what I have on hand is important to our financial goals (cash out of pocket life!) and this week I seem to have a lot of rhubarb I quick froze last fall still hanging around.

We love a good rhubarb crisp and of course Rhubarb Dream Bars but I needed a recipe to use up some of that huge box of oatmeal too. I turned to an old favorite recipe reminiscent of bars our local coffee shop sells for 3 bucks a pop. They use raspberries or raspberry jam but that’s just not happening, so Rhubarb Oatmeal Bars it is.

Rhubarb Oatmeal Bars

This recipe for Rhubarb Oatmeal Bars will get that last bag of rhubarb right out of the freezer. Pair it with another pantry staple, oatmeal and you've got cookies you can make just about anytime.
Prep Time20 mins
Cook Time35 mins
Total Time55 mins
Course: Dessert, Snack
Cuisine: Alaskan, American
Servings: 24 bars


  • 2 cups of flour
  • 2 cups of quick cook oats
  • 1 1/3 cups of brown sugar
  • 1/2 tsp baking soda
  • pinch salt
  • 1 cup butter
  • 4 cups rhubarb
  • 1/4 cup water if you're rhubarb was frozen you probably won't need this
  • 1 cup Sugar more or less if you prefer sweeter or tangy
  • 4 TBSP flour


  • Preheat the oven to 350˚ Make the Crust/Topping:
  • mix the dry ingredients together
  • cut the butter in chunks and drop it in the dry mix, cut in with a pastry blender or two knives, or use your hands mix it in
  • keep mixing until it looks like coarse crumbs
  • save off 1 cup of crumbs
  • press the rest in the bottom of a 9X13 baking dish
  • Make the Rhubarb Filling
  • put the rhubarb, water (if using) and sugar in a sauce pan
  • bring it to a boil over medium high heat, it will get very juicy as it cooks
  • once it comes to a boil reduce the heat to keep it from scorching, just keep it bubbling lightly until the rhubarb is just starting to get soft
  • remove 2/3 cup of the juice and whisk in the flour into it
  • add it back in the pan and stir until thickened, cook and stir for 1-2 minutes and remove from the heat (you just made rhubarb gravy!)
  • spread the rhubarb over the base layer in the 9X13 sprinkle with reserved crumbs
  • bake for 30-35 minutes until top is lightly brown and the rhubarb is bubbly
  • let it cool before you cut it for best results
See the different layers in these bars?? Perfect base, filling and topping ratio!

Cookies for Lunches

This recipe uses a fair amount of each excessive pantry bulk item, 4 cups of rhubarb and 2 cups of oatmeal, so I feel quite good about using up what we already have. Its one of the ways I make our dollars stretch as far as possible every day. I never run to the store to grab ________ I just make do without it and use what we have. Also rhubarb and oatmeal go really well together and I sent them in the kid’s lunches and they travel well too. If you plan to send them with kids, they seem to hold up better if they’re cut bigger than what I have pictured, about double that size and they travel better. I don’t know, maybe your kids don’t swing their lunch boxes all the way around their head while belting out a Norse battle cry??

A few notes on these bars:

• if you’ve got frozen rhubarb more than likely you won’t need the 1/4 cup of water it won’t hurt either way, so use it if you feel like you’re rhubarb is dry
• don’t cover for storage these unless you want them to revert to a mushy me

Rhubarb Bars