Tart rhubarb, crunchy brown sugar and oats, cinnamon, and nutty buckwheat flour. Gluten-free rhubarb crisp is everything you want in a rustic-but-gorgeous dessert!
I recently fell in love with pie making, but let’s get real, baking a pie takes way longer than throwing together a crisp! Crisps are one of my all-time favourite ways to use up fresh or frozen fruit, and this gluten-free rhubarb crisp is a knockout winner.
We are not a gluten-free household, however, we have gluten-intolerant family members. That being said, we also just really like the flavour and texture of alternative flours. I bake with buckwheat, and brown rice flour often!
Here’s What You Need To Make Gluten-Free Rhubarb Crisp:
For The Rhubarb Filling:
- fresh rhubarb
- lemon juice
For The Gluten-Free Crisp Topping:
- brown sugar
- buckwheat flour
- large flake oats (certified gluten-free if needed)
Using Fresh Vs. Frozen Rhubarb
I’ve made this gluten-free rhubarb crisp using both frozen and fresh rhubarb, with no real difference. If you want to use frozen rhubarb, there’s no need to thaw it first. Just note that the sugar and cornstarch mix won’t “stick” to frozen rhubarb like it does to fresh when you stir them together.
How To Freeze Rhubarb
Freezing chopped rhubarb on a baking sheet makes it easier to bake with later on. After it’s been frozen, I portion my rhubarb into pre-measured amounts. My favourite way to freeze rhubarb is:
- Chop rhubarb stalks into ½-inch (1-cm) pieces.
- Find a baking sheet, or something else flat, that will fit in your freezer, and line it with parchment paper.
- Spread the rhubarb evenly on the baking sheet.
- Freeze the rhubarb for 2 to 3 hours.
- Portion the now frozen rhubarb into 2 cup (300g) servings. Store in a plastic zipper bag, or airtight container, and return to the freezer for future use.
I also repeat the same method – spreading the rhubarb on a baking sheet, freezing, then portioning – with ¼-inch (5-mm) chopped pieces. Both ½-inch (1-cm) and ¼-inch (5-mm) sized pieces are great for baking.
One cup of chopped rhubarb weighs approximately 150 grams.
A Few Notes About The Ingredients:
- Rhubarb – As mentioned, fresh or frozen rhubarb will work for this gluten-free rhubarb crisp. Make sure you wash your rhubarb before chopping to rinse away any dirt, or tiny critters hanging on.
- Lemon Juice – Lemon juice adds a touch of brightness which compliments the tart acidity of the rhubarb. If you don’t have fresh lemon use bottled.
- Sugar – I’ve made gluten-free rhubarb crisp with both white sugar and organic cane sugar. If sugar is a concern, you can reduce the amount of sugar slightly, however, sweetness will balance the sour rhubarb. If you reduce the amount of sugar be prepared for your lips to pucker!
- Cornstarch – I chose cornstarch as the thickener for this gluten-free rhubarb crisp. Arrowroot or tapioca starch are also good options. If gluten isn’t an issue for you can also swap in all-purpose flour.
- Buckwheat Flour – I love to bake with buckwheat flour and always have it on hand. I’ve made this recipe with brown rice flour as another gluten-free option. I haven’t tried them, but I feel like oat or amaranth flour would also work here. And of course, once again, if gluten isn’t an issue you can substitute all-purpose flour.
- Oats – Use certified gluten-free oats to keep this recipe gluten-free.
Tips & Suggestions For Making Gluten-Free Rhubarb Crisp
- Use A Scale – Use a scale to weigh ingredients if you have one. A scale ensures accuracy and consistency, and increases the chance of a recipe turning our perfectly the first time.
- Mixing The Rhubarb And Cornstarch – I prefer to mix the sugar and cornstarch together in a small bowl before mixing with the rhubarb. I get an even, lump-free coating on the rhubarb when I do it this way.
- Pan Size – I tested this crisp recipe in an 8-inch (20-cm) square pan. An 8-inch (20-cm) round baking dish will also work.
- Make Ahead Option – You can make this crisp ahead of time, just make the recipe as written, but don’t bake the crisp. Instead, keep the it covered in the fridge for a day or two until you’re ready to bake. You can also keep it, tightly covered in the freezer for up to one month. If your make ahead crisp is kept in the fridge, let the dish come to room temperature for 30 minutes before baking. If you choose to freeze the unbaked crisp, do not make it in a glass dish – it could potentially explode in a hot oven. Use a metal or disposable foil pan instead. In a metal or aluminum pan you can bake the crisp directly from frozen. Set the timer for the allotted time specified in the recipe. Once that time is up keep your eye on the topping and the rhubarb filling. When the topping is golden, and the filling is bubbling, it’s done.
- Make It Vegan – Make a plant-based gluten-free rhubarb crisp by substituting vegan butter for butter.
Other Spring Rhubarb Recipes You Should Try!
Rhubarb Curd Creamy, tart, and sweet, use it on toast, ice cream, stir it into yogurt, spread it between cake layers, and so much more.
Maple Rhubarb Jam With Cardamom Lightly sweetened with maple syrup, this is a gorgeous small batch ruby red jam.
Rhubarb Fool With Cardamom Cream Layers of poached rhubarb and cream make for a show stopping dessert!
Apple Rhubarb Pie A beautiful way to showcase late winter apples and early spring rhubarb.
For The Rhubarb Filling
- 4 cups (600g) rhubarb, chopped into ½-inch (1-cm) pieces
- 2 teaspoons lemon juice
- ½ cup (100g) white sugar
- ¼ cup (30g) cornstarch
For The Crisp Topping
- ½ cup (80g) buckwheat flour
- ½ cup (113g) brown sugar
- ½ cup (45g) large flake oats
- 1 teaspoon cinnamon
- pinch salt
- ½ cup (113g) butter, room temperature
- Preheat the oven to 350ºF / 180ºC. Grease a square 8-inch (20-cm) baking pan with butter.
- Make The Rhubarb Filling - In a large bowl stir the rhubarb and lemon juice together. Mix the sugar and cornstarch together separately in a small bowl with a fork then sprinkle it all over the rhubarb. Stir the rhubarb well to coat and set aside.
- Make The Crisp Topping - In another bowl mix the buckwheat flour, brown sugar, oats, cinnamon, and salt together. Use your hands to rub the butter into the buckwheat mixture until it is coarse and sandy with some larger bits of butter.
- Spread the rhubarb evenly into the prepared pan. Sprinkle the topping on top and spread it out evenly across the rhubarb. Bake the crisp for 40-45 minutes or until the top is golden, and the rhubarb is bubbling.
Amount Per Serving: Calories: 160Total Fat: 6gSaturated Fat: 3gTrans Fat: 0gUnsaturated Fat: 0gCholesterol: 0mgSodium: 27mgCarbohydrates: 8gFiber: 1gSugar: 18gProtein: 1g
DISCLAIMER - NUTRITIONAL DATA IS PROVIDED BY A CALCULATOR AND IS A ROUGH ESTIMATION OF THE NUTRITIONAL INFORMATION IN THIS RECIPE.