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Rhubarb Crisp with Apples and Oatmeal

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Amazingly aromatic rhubarb apple crisp with crunchy oatmeal and brown sugar topping, this is one of the best rhubarb desserts ever.

Rhubarb Crunch with Apples

Make the most of the short rhubarb season with this tangy rhubarb apple crisp, which can be served either warm or at room temperature, as it is or with a nice vanilla custard or vanilla ice cream.

plate with rhubarb apple crisp - Where Is My Spoon

I do have a soft spot for this kind of dessert, either crisp or a crumble like my favorite apple crumble, a pudding with custard, like this Baked Rhubarb Custard or a fruit casserole like this Kirschmichel – Cherry Casserole.

Over the years I have made so many fruit crumbles or fruit crisps, I have really lost track of all of them. The one I make the most is apple crumble, apples are always so reliable and available, but when the season allows it, I make rhubarb crunch or crumble.

rhubarb crisp in a casserole dish - Where Is My Spoon

Difference between a crisp and a crumble?

  • Actually a crisp and a crumble are very similar, crumble being a name used mostly in the UK.
  • However, there is a small difference between the two: a crisp is usually made with oatmeal/ oats, while a crumble is a streusel-like topping, made with flour (all-purpose or whole-wheat), sugar (white or brown) and butter.
  • The crumble topping I use to make a fruit crumble is generally the same one I use when making a crumble cake or crumble pie. I sometimes add almonds flakes to it as well.
  • Another difference would be that, as the name already says it, a crisp would be crispier, due to the oats that crisp up during the baking process.
  • Another similar dessert is cobbler. The cobblers are fresh fruit in a casserole dish, topped with a biscuit topping. Other versions of cobblers are made with cake batter (like this Easy Red Currant Cobbler with Almonds) or with cookie dough.

Rhubarb crisp with frozen rhubarb

Can you make the rhubarb crisp with frozen rhubarb?

  • You can definitely do so. The recipe will instruct you to sprinkle the rhubarb pieces with sugar and leave the fruit to release its juices. These juices will be discarded before making the crisp, otherwise, the crisp will not be crispy, but rather soggy.
  • Frozen fruit usually releases more water than fresh fruit, but this will not be an issue in the case of this rhubarb apple crisp, as you will drain everything anyway.
rhubarb apple crisp - Where Is My Spoon

How to freeze rhubarb?

I freeze a lot of rhubarb, at least 2 or 3 large bags every spring. And I use it to make all the above-mentioned recipes as well.

  • Chop the rhubarb into small pieces, as you would normally chop it for a cake or something, place the pieces in a freezer bag, flatten the bag a little and freeze.
  • Martha Stewart would advise you to place the chopped rhubarb on baking trays lined with baking paper, freeze it in this manner for several hours and then transfer the frozen pieces to freezer bags. A very good approach, definitely, this way the rhubarb slices will not stick together when frozen.
  • But, to tell you the truth, I don’t have either the patience for this extra work nor enough space in my freezer for a large baking tray. So, I don’t do it!
  • My frozen slices do stick together, so whenever I need rhubarb I either defrost a whole bag or, if I need less, I smash the bag once or twice or my kitchen marble counter. It works like a charm! 🙂 I do that not only with rhubarb but with frozen berries, chickpeas or beans as well.
  • The rhubarb slices/berries/beans will separate and I will be able to take out as much as I need. And I really don’t care if a few slices will get squashed in the process, the majority will remain intact.
plate with rhubarb apple crisp - Where Is My Spoon

How to make?

  • First of all, discard the leaves, they are poisonous!
  • According to Wikipedia, “rhubarb leaves contain poisonous substances, including oxalic acid, which is present in many plants. Humans have been poisoned after ingesting the leaves, a particular problem during World War I when the leaves were mistakenly recommended as a food source in Britain”.
  • This recipe is very easy, like all crisp, crumble or cobbler recipes.
  • The only thing you have to make sure of is that you drain the slices well before you add them to the baking dish. Too much juice will make the crisp soggy.
  • The addition of some cornstarch will also help against the sogginess, the slices should be coated in a thin layer of cornstarch.
  • To make the crisp I used a mixture of brown and white sugar, I thought the brown sugar adds a little bit of extra flavor, gives the crisp a light caramel touch. However, that is not a must, if white sugar is all you have, replace the brown sugar with it.
how to make rhubarb crisp - Where Is My Spoon
how to make rhubarb crisp - Where Is My Spoon

How to serve?

  • You can have the rhubarb apple crisp just as it is, either warm or at room temperature.
  • Or you can have it warm with a dollop of vanilla ice cream that will melt slowly on top of it and bring it to a whole new level.
  • You can also top the dessert with whipped cream, runny cream, vanilla sauce or custard.
  • Or a personal favorite of mine: mix some creme fraiche with a little brown sugar, let the mixture stand for a short while until the brown sugar dissolves in the crème fraiche. A divine combination!
rhubarb crisp - Where Is My Spoon
rhubarb crisp with oats and apples being served with a spoon

Rhubarb Apple Crisp with Oatmeal

Amazingly aromatic rhubarb crisp with apples, topped with a crunchy oatmeal and brown sugar topping, this is one of the best rhubarb desserts ever.
4.23 from 9 votes
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Course: Desserts
Cuisine: American
Prep Time: 30 minutes
Cook Time: 30 minutes
Total Time: 1 hour
Servings: 4 -6
Calories: 548kcal
Author: Adina


  • Rhubarb apple mixture:
  • 2 kg/ 4.4 lbs rhubarb
  • 100 g/ 3.5 oz/ ½ cup white sugar
  • 2 medium apples about 300 g/ 10.6 oz
  • 1 teaspoon vanilla extract
  • 3 tablespoons cornstarch
  • Crisp:
  • 100 g/ 3.5 oz/ 1 cup oats
  • 60 g/ 2.1 oz/ ½ cup all-purpose flour
  • 90 g/ 3.2 oz/ ½ cup brown sugar Note
  • 100 g/ 3.5 oz/ ½ cup white sugar
  • a pinch of salt
  • 120 g/ 4.2 oz/ ½ cup unsalted butter cold


Rhubarb mixture:

  • Clean the rhubarb and chop it into 2 cm/ ¾ inch pieces. Place in a bowl and sprinkle with sugar. Mix well and let the rhubarb release its juices for about 15-20 minutes.
  • In the meantime, preheat the oven to 180 degrees Celsius/ 350 degrees Fahrenheit, chop the apples into small cubes and make the crisp.
  • Drain the rhubarb well, add the chopped apples, vanilla extract, and cornstarch and mix well. Place in a casserole dish of about 20×32 cm/ 8×12 inches.


  • Place the oats, flour, both types of sugar and salt in a bowl. Mix well.
  • Cube the cold butter and add it to the mixture. Stir to coat the butter cubes in the flour and oat mixture, then cut in the butter using two knives or rub the butter into the mixture using your fingertips.
  • Spread the crisp mixture on top of the rhubarb in the casserole dish.


  • Bake for 15 minutes in the preheated oven, then lower the heat to 160 degrees Celsius/ 320 degrees Fahrenheit and continue baking it for 15 more minutes or until golden brown.
  • Serve warm or at room temperature with one of the above-mentioned toppings.


You can use only white sugar instead of a mixture of brown and white sugar. Just replace the brown sugar with the same amount of white sugar.


Serving: 1/6 of the dish | Calories: 548kcal | Carbohydrates: 94g | Protein: 7g | Fat: 18g | Saturated Fat: 11g | Polyunsaturated Fat: 7g | Cholesterol: 43mg | Sodium: 22mg | Fiber: 9g | Sugar: 58g
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Recipe Rating


Friday 25th of May 2018

It's just the perfect late spring recipe :)


Friday 25th of May 2018

Oh my, can't really resist this, love the idea of putting rhubarb and apple together.


Thursday 24th of May 2018

mmm...can't resist anything with streusel!


Tuesday 9th of June 2020

Are you kidding - 4.4 pounds of rhubarb? Really? Fix this recipe for beginners to use. Lauri