This roasted rhubarb apple crisp recipe is so simple – with only 6 ingredients and minimal prep time, it is the perfect springtime dish. The crisp topping is based on oats, and is free of refined flour and refined sugar, making it a healthy high-fibre dessert.
Why roast the rhubarb you may ask? Simply to save on dishes and prep time. A conventional rhubarb crisp will require that the rhubarb and apple be cooked on the stovetop to break down prior to putting in the oven with the oatmeal topping. By baking the rhubarb and apple first you cut back not only on dishes but also time spent in the kitchen. This is one of my favourite crisp toppings – I’ve finally mastered the flour-free crisp and I am so excited for you to try it!
Why I Made This Roasted Rhubarb Apple Crisp
This Is A Healthy Crisp
I love sharing healthy dessert recipes because they often taste just as good as the non-healthy option (like my Seedy Peanut Butter Oatmeal Cookies). The crisp topping is made only from oats, coconut oil and honey. I like adding a little bit of coconut flakes for texture, but any nut or seed can be used as well.
This Is A Diabetic Friendly Crisp
This crisp is sweetened with honey which has a lower glycemic index than regular sugar, making it a better choice for blood sugar levels. It is also flour-free, and instead uses oats that have been ground up into ‘oat-flour’. Oats are a great replacement for flour (see my post Three Ingredient Banana Pancakes) and are a great low glycemic index choice. This crisp contains 32 grams of net carbs, making it a suitable diabetic dessert if served with some high protein Greek yogurt.
This Crisp Is Vegan
No animal products here. I love using coconut oil in place of butter to add to the flavour of the coconut, which goes so nicely with the rhubarb and apple combination. Serve it with some dairy-free ice cream – coconut ice cream is my favourite!
This Is A Rhubarb Apple Crumble with Oats
This crisp is based on oats, and whole oats are used in the topping along with oat flour. You can make oat flour at home by blending your regular oats in a small blender. You can also purchase oat flour from most grocery stores.
Tips For This Roasted Rhubarb Apple Crisp
Making A Sweeter Crisp
I love the tartness of rhubarb and therefore do not add additional honey to the roasting rhubarb and apple. If you are serving this to guests who may have a sweet-tooth, add 1 tablespoon of additional honey to the rhubarb and apple before roasting.
How To Make Oat Flour
I use my small Nutra Bullet to make just enough oat flour for whatever I am making. When you are measuring out whole oats you will measure out more than the quantity of oat flour you need. As an example, for this recipe, you would measure out about 1/3 cup of whole oats to make 1/4 cup of oat flour. This is because the oats become more condensed after blending
Using Coconut Flakes
I used large coconut flakes for texture, but feel free to use the smaller coconut flakes if that is what you have on hand. Choose unsweetened coconut flakes.
Leaving The Skin On The Apples
I like to leave the skin on the apples as this increases the overall fibre of the dish, making it easier on our blood sugar levels. The skin and the flesh of the apple just under the skin is also where many of the important nutrients are.
Notes For This Roasted Rhubarb Apple Crisp
Making A Gluten-Free Crisp
This crisp is naturally gluten-free because it does not use regular flour. If you are serving it to someone who has celiac disease, just make sure that the oats are certified gluten-free, as oats can potentially become contaminated during processing.
Making A Vegan Crisp
This crisp uses coconut oil in place of butter for a vegan alternative. For strict vegans who avoid honey, replace the honey with 1/3 cup of maple syrup. Serve it with some vegan ice cream or vegan yogurt in place of regular ice cream or yogurt.
Alternatives to Coconut Flakes
The coconut flakes add some texture to the crisp topping and if you don’t have coconut flakes on hand, you can substitute them out for some nuts. Try adding some chopped pecans or almonds to the crisp topping before baking.
What To Serve This Rhubarb Apple Crisp With
I love serving this crisp with some coconut-based ice cream. For those who have dairy, they might choose some plain yogurt, Greek yogurt or regular ice cream. The high protein content of the Greek yogurt helps to reduce any blood sugar spikes from the fruit, honey and oats by slowing down the digestion of these carbohydrates into sugar.
Variations For This Rhubarb Apple Crisp
Making A Rhubarb Strawberry Crisp
Strawberries do not need to be roasted ahead of time. If substituting in strawberries for the apples, roast the rhubarb as per recipe directions and then add 3 cups of halved strawberries and top with crisp topping and bake for 20 minutes.
Making A Rhubarb Blueberry Crisp
The same with strawberries, blueberries do not need to be roasted ahead of time. Add 2 cups of blueberries after the rhubarb has been roasted, and then top with the crisp topping.
Making A Rhubarb Saskatoon Berry Crisp
If you’re lucky enough to get your hands on saskatoon berries, you can substitute in 2 cups of Saskatoon berries for the apples. Add the berries to the already roasted rhubarb. I suggest drizzling over 1 tablespoon of additional honey to sweetened the fruit mixture, before adding the crisp topping.
Want Some More Recipes Featuring Oats?
Oats are a great base for desserts as they add beneficial soluble fibre and can replace refined flours in many desserts. Here are a few of my favourite dessert recipes featuring oats.
- Seedy Peanut Butter Oatmeal Cookies
- Easy Almond Butter Chocolate Chip Cookie
- Tahini Coconut No-Bake Energy Balls
Want Some More Healthy Dessert Recipes?
Healthy dessert doesn’t need to be boring. Here are some of my favourite healthy dessert recipes. Try these favourite dessert recipes:
- Raw Chocolate Date Bar
- Three Ingredient Peanut Butter Cookies
- Raw Chocolate Brownies with Caramel Icing
Roasted Rhubarb Apple Crisp | Vegan Gluten-Free
- 5 stalks rhubarb
- 5 small apples or 3 medium
- 1 cup oats traditional
- 1/4 cup oat flour (or 1/3 cup of traditional oats for making flour)
- 1/4 cup honey (or 1/3 cup of maple syrup for a vegan version)
- 2 tbsp coconut oil
- 1/4 cup coconut flakes large, unsweetened
- Preheat the oven to 350°F. Grease a baking sheet with coconut oil or line it with parchment paper.
- Wash the apples and slice off the four quadrants and dispose of the core. You can leave the skin on as this contributes to more fibre. Dice the apple into small 1/2 inch pieces and place on the baking tray.
- Wash the rhubarb and remove any discoloured ends. Cut the rhubarb into small pieces - if the stalks are thick you may have to slice them lengthwise first, and then dice them. Add the diced rhubarb to a baking tray on top of the apples.
- *You have the option here of adding an additional 1 tablespoon of honey (or maple syrup) on top of the diced fruit for a sweeter crisp. I do not add honey to the fruit.
- Place the baking tray of chopped apple and rhubarb into the preheated oven and bake for 15 minutes.
To Make The Crisp Topping
- While the fruit is baking, make the crisp topping. First, if you are making the oat flour at home add 1/3 cup of whole oats to a small blender and blend until a fine flour is formed. If you are purchasing oat flour you can skip this step.
- Next, melt the coconut oil on the stovetop. Add the melted coconut oil to the 1 cup of oats, 1/4 cup of oat flour, 1/4 cup coconut flakes and 1/4 cup of honey (or 1/3 cup of maple syrup) and mix until well combined.
- When the fruit is finished baking remove it from the oven. Add the crisp topping evenly over the roasted fruit. Return the baking tray to the oven and bake for an additional 20 minutes.
- You will know the crisp is done when it is nice and golden on top. Let cool slightly before serving. Serve with some coconut-based ice cream or yogurt. Store leftovers in the fridge.
Making A Gluten-Free CrispThis crisp is naturally gluten-free because it does not use regular flour. If you are serving it to someone who has celiac disease, just make sure that the oats are certified gluten-free.
Alternatives to Coconut FlakesThe coconut flakes add some texture to the crisp topping, you can use small or large unsweetened coconut flakes. If you don't have coconut flakes on hand, try adding some chopped pecans or almonds to the crisp topping before baking.
What To Serve This Rhubarb Apple Crisp WithI love serving this crisp with some coconut-based ice cream. For those who have dairy, they might choose some plain yogurt, Greek yogurt or regular ice cream.
Want To Pin This Rhubarb Crisp Recipe For Later?
Rachel Dickens, The Conscious Dietitian, is a Registered Dietitian and Certified Diabetes Educator. She graduated with her Masters in Nutrition and Dietetics in 2010 from Griffith University. She strives to provide evidence-based nutrition information with a focus on plant-based nutrition and share some of her favourite seasonal recipes and sustainable eating tips.