Best (Easy) Vegan Rhubarb Crumble Recipe With Oats

Name: Easy Vegan Rhubarb Crumble
Prep time: 15 min
Cook time: 40 min
Total time: 55 min
Ingredients: 8 c Rhubarb (Chopped into 1/2" pieces); 1 c Brown Sugar (Packed); 3 tbsp All Purpose Flour; 2 tsp Vanilla Extract; 1/4 tsp Salt; 1 c Quick Oats; 3/4 c All Purpose Flour; 3/4 c Brown Sugar; 1 tsp Cinnamon; 1/2 tsp Baking Powder; 1/2 c Vegan Margarine, melted

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Last Updated on June 6, 2023 by Sabrina Currie

It's rhubarb season!!! (Or maybe you have some frozen to use up.) Either way, this rhubarb recipe is of my favorite rhubarb desserts using this flavorful, fruit-like veggie. Vegan rhubarb crumble with oats is ultra easy and uses just 9 basic, easy-to-find ingredients.

Close up side view of bright red baked rhubarb with warm brown crumb topping. Recipe title is above in white writing over pink background. This image is for pinning to Pinterest.

Why You Should Make This Recipe

All the flavor of rhubarb pie without having to make a pie crust or pastry! It comes together fast with hardly any mess. This great recipe to use sweet, tart rhubarb and it's easy for any age to make.

While a traditional crumble is topped with just flour, sugar and butter, adding a little oatmeal to the crumble topping adds extra flavor and texture to the soft, sweet-tart filling beneath.

For more rhubarb dessert ideas, try Rhubarb Snack Cake with Yogurt and Olive Oil, Ultimate Strawberry Rhubarb Shortcake, and Strawberry Rhubarb Oatmeal Muffins. For a fun savory rhubarb recipe, try this vegan Rhubarb Salsa.

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Why You Should Make This Recipe
Recipe Ingredients
Substitutions + Variations
Step-by-Step Instructions
Expert Tips
Recipe FAQs
More Vegan Fruit Recipes
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A forkful of rhubarb crumble being lifted up with juicy drips of rhubarb juice spilling off.

Rhubarb is easy to grow in temperate climates or you can pick up rhubarb stalks at your local farmers market or grocery store during the spring and early summer months.

With all the fresh fruit and oats, I think this qualifies as a healthy dessert or even a perfect addition to breakfast. Don't you agree?!

Recipe Ingredients

With just 9 basic ingredients in this recipe including delicious tangy rhubarb, it comes together fast. Delicious for company but easy enough for a weeknight dessert. Serve it up with some coconut whipped cream or vegan vanilla ice cream

Text labelled rhubarb crumble ingredients including rhubarb, brown sugar, cinnamon, salt, baking powder, vanilla, oats, flour and margarine.

Oats - I use quick oats for baking because I like their texture. It's hearty without being overwhelming. Stone ground oatmeal will work too but gives a little more toothsome bite. While a true crumble omits oats (but sometimes includes nuts) this one has both flour and oats for a really delicious combination. Feel free to call it a vegan rhubarb crisp too!
Margarine - A hard block of vegan butter or margarine works best for almost all baking. It behaves just like dairy butter and that is what I recommend. But...this recipe is quite forgiving and you can substitute soft tub margarine or even coconut oil in a pinch. I melt mine in a heat-safe, small bowl in the microwave.
Rhubarb - This vegan rhubarb crumble will work equally well with fresh rhubarb or frozen rhubarb. Rhubarb is quite tart so sugar is necessary. I've made this with minimal sugar so if you prefer a more sweet rhubarb dessert, you can add an extra ¼-1/2 cup of brown sugar to the rhubarb mixture before pouring into the baking dish.

See recipe card for quantities.

Substitutions + Variations

Sugar - You can swap the brown sugar at a 1 to 1 ratio for demerara sugar or coconut sugar. To substitute white sugar, use 1 cup in the rhubarb mixture and ½ cup in the crumble topping.
Vegan Strawberry Rhubarb Crumble - Fresh fruit crumbles are the best and this is easy to change up. Swap out 2 cups of rhubarb for 2 cups of halved fresh strawberries and complete recipe as written for a classic dessert combination. If using frozen strawberries, add an extra tablespoon of flour to the fruit mixture to account for the extra juice that will come out of the frozen berries while baking.
Vegan Rhubarb Crisp Pie - Bake up this easy recipe in 2 pie plates for rhubarb crisp pie! Simply pour half the rhubarb mixture into each of the 2 pie pans and top with half the crumble mixture in each pan. Reduce baking time to 30-35 minutes until the rhubarb 'pies' are golden brown on top and the rhubarb filling is juicy and bubbling.

Step-by-Step Instructions

Start by preheating your oven. Next chop the rhubarb and toss it with the sugar and flour so it can start to get juicy while you prep the topping. You can prepare the sugar rhubarb mix early in the day, up to 6 hours ahead if you like.

Step one, rhubarb is cut into small pieces and is in a white bowl.

Step 1. Preheat oven to 350º
Add chopped fresh rhubarb (or frozen rhubarb if using) to a large mixing bowl. I chop mine into half-inch pieces.

The bowl of chopped rhubarb has white flour and brown sugar poured in but not yet stirred.

Step 2. Add in the brown sugar, vanilla, salt and flour.

Flour and sugar have been stirred into the bowl of cut rhubarb and it has a grainy and glazed look to it.

Step 3. Stir to combine and set aside while you make the crumble topping.

Flour, brown sugar, cinnamon, baking powder and oats have been added to a blue bowl.

Step 4. In a medium bowl, add the rest of the dry ingredients (oats, remaining flour and brown sugar, cinnamon and baking powder).

Dry ingredients have been stirred together and are a pale tan color in the blue bowl.

Step 5. Stir the dry ingredients together well.

Yellow melted margarine is being poured into the dry oatmeal mixture.

Step 6. Pour melted margarine over oatmeal mixture.

Butter and oat mixture has been stirred together well and is a medium brown wet looking mixture.

Step 7. Stir until well combined. It will be a little crumbly and that is fine.

Chopped and macerated rhubarb and sugar mixture is in a glass 9 x 13" pan.

Step 8. Dump rhubarb filling ingredients into a 9"x13" casserole dish or high sided baking pan. (You do not need to grease the pan, though if you prefer, you can line your baking dish with parchment paper.)

9 x 13" glass baking dish of rhubarb chunks is covered with the buttery oatmeal crumble topping, ready to bake.

Step 9. Sprinkle the crumble evenly all over and place in the oven to bake.

Close up of bubbly pink rhubarb along the edges of the crumble in the pan.

Step 10. Bake at 350'F for 40 minutes, until top is golden brown and rhubarb is tender, juicy and slightly thickened.
Serve warm with vegan vanilla ice cream or whipped cream.

Cubes of bright pink rhubarb spilling out of a the nut brown crumble topping on a black plate.

Expert Tips

This vegan rhubarb crumble keeps really well for 3 days but will continue to keep safely for 5 days. Store it in an airtight container or cover the baking dish with plastic wrap. Reheat for 10 minutes in a 350' oven to crisp up the topping right before serving.

Recipe FAQs

Do you need to peel rhubarb?

No. Rhubarb is so easy to prepare. Simply wash the stalks, trim any brown bits off the top or bottom and it's ready to use! Rhubarb freezes well too. I love to chop mine up ready for a recipe and freeze it in zip top bags. Most recipes work just as well with frozen rhubarb as they do with cubed fresh rhubarb.

Should rhubarb be cooked before baking?

No, at least not usually. This recipe cooks it from raw or even frozen and most use it this way. Some recipes cook the rhubarb first so read your recipe well before starting.

More Vegan Fruit Recipes

I love using seasonal fruits in my recipes. If you love this vegan rhubarb crumble, check out these other vegan fruit recipes below or search through all my fruit recipes for more great baking ideas.

A black plate with golden brown crumble topped red rhubarb dessert.

If you have any questions or comments, you can find me on Instagram, Pinterest and Facebook. I try to answer any recipe related questions quickly as I know you might be in the middle of making it.

Also check out my FREE PRINTABLE meal planner to make menu planning and grocery shopping a breeze and my shopping guide. And if you like this recipe, I would love it if you give it a star rating in the recipe card.

Cheers and happy cooking, Friends! Sabrina

If you have any questions or comments, you can find me on Instagram, Pinterest and Facebook. I try to answer any recipe related questions quickly as I know you might be in the middle of making it.

Cheers and happy cooking, Friends! Sabrina