Old-Fashioned Rhubarb Crisp with a Thick Oat Topping

This easy rhubarb crisp recipe has the just the perfect combination of tangy rhubarb mixture with a generous, thick crisp topping. I mean it…it’s the BEST way to make rhubarb desserts!

I know everyone claims that their recipes are the BEST EVER. But, seriously, I mean it! (tee hee)

When my husband walked in the door the other day with a bag full of rhubarb we’d been gifted, I knew exactly what I was making first:

Mom’s Rhubarb Crisp is my all time favorite way to use rhubarb. Her old-fashioned rhubarb recipe is such an easy one and makes a perfect & special dessert.

I’ve tried many crisps in my day, and I still say this is the best rhubarb crisp recipe ever. Although sweet desserts involve a lot of personal preference, I find it has just the perfect balance of sweetness to the tart rhubarb, and the thick buttery oat topping makes it the best ever!

Why You’ll Love this Old Fashioned Rhubarb Crisp Recipe

• Perfect Sweet-Tart Balance – The right amount of sugar brings out the best in fresh rhubarb.
• Generous, Thick Crisp Topping – No skimpy topping here! It’s rich, buttery, and just the right amount of crunchy.
• Simple Ingredients – Made with pantry staples for an easy and delicious homemade dessert.
• Great for Spring & Summer – A perfect way to use fresh rhubarb from the garden or farmer’s market.
• Easy to Make Ahead – Prep the filling and topping in advance for a quick dessert anytime.

Ingredients for Rhubarb Crisp 9×13 pan:

(See the printable recipe card below for exact measurements and instructions!)

• Rhubarb – Fresh or frozen, chopped into bite-sized pieces.
• Granulated White Sugar – Balances rhubarb’s natural tartness and draws out its juices.
• Flour – Helps thicken the fruit filling.
• Brown Sugar – Adds a deep, caramel-like sweetness to the crisp topping.
• Oats – Gives the topping a delicious, crunchy texture.
• Butter – The key to a rich, buttery crisp topping.

How to Portion, Cook, and Freeze This Recipe to Fit Your Lifestyle

Making for Two? Halve the ingredients and bake in an 8×8-inch dish.
Freezing Ahead Unbaked? Assemble the crisp, cover tightly, and freeze unbaked. Let it sit at room temperature for 15 minutes before baking to ensure even cooking. Bake according to directions, adding about 10-15 minutes extra baking time.
Freeze Ahead Baked? Prepare according to directions and then freeze tightly covered. Thaw and reheat when ready to use.

Step by Step Instructions for Rhubarb Crisp

Kitchen Hack: Use Melted Butter for Crisp Toppings!

I recently learned a little hack for making crisp toppings even quicker and easier. Of course you can cut in the butter with a pastry blender and it will work great. Or, you can melt the butter, mix it into the dry ingredients, and then place the topping in the fridge to cool while you prepare the fruit filling. I now use this technique with all my crisp recipe.

Here’s a litttle video that demonstrates it:

Tips for Rhubarb Crisp

• Use fresh or frozen rhubarb – No need to thaw frozen rhubarb; just add a few extra minutes to the bake time.
• Melted butter shortcut – Instead of cutting in cold butter, melt it and mix it into the dry ingredients for a quick and easy crisp topping.
• Let it cool slightly before serving – This helps the filling set up and makes it easier to scoop.

For more delicious desserts recipes, you might want to check out these:

• If you’re looking for another rhubarb recipe, you’ll love this baked sticky rhubarb pudding.
• Quick & easy apple crisp with apple pie filling
• Grandma’s Strawberry Pie with Jello
• You’ll love this classic recipe – lemon meringue pie
• Banana cream pie just like my mom made
• You’re Going to Want to Try this Rhubarb Cake Recipe!
• Pumpkin bread with cake mix
• You’ll love this peach crisp recipe!

Save this rhubarb crisp recipe to your favorite dessert board on Pinterest, and follow me for more delicious recipes!