Easy Blueberry Rhubarb Crisp Recipe to Use Year Round

Looking for a great way to use frozen blueberries and frozen rhubarb? Make an easy blueberry rhubarb crisp recipe with frozen or fresh blueberries and rhubarb. Since you can use frozen fruit, his simple blueberry rhubarb crisp recipe may be enjoyed any time of the year.

In my continued quest to use the produce stored in my big freezer from last year, I used some frozen rhubarb to make pineapple rhubarb jam and tangy rhubarb orange jam. I’m also on a continuous quest to find more ways to use frozen berries, and have made raspberry blueberry jam, blueberry syrup, blueberry cobbler, blueberry hand pies, berry gelato, and blueberry lime jam. Now, I’m going to have blueberries and rhubarb join together in an easy blueberry rhubarb crisp recipe. What can you do with fresh rhubarb? This rhubarb blueberry crisp recipe works with fresh rhubarb and blueberries as well.

I’m fortunate that rhubarb and blueberries both grow well in our garden. In this recipe for frozen blueberry rhubarb crisp, I use the same basic recipe as I used for my easy apple crisp recipe. The blueberry rhubarb crisp recipe with oats in the topping is hard to resist. Since it’s not a recipe for rhubarb by itself in a crisp, I was able to use the same amount of sugar as in the easy apple crisp. The best recipes for rhubarb crisp might have to use quite a bit of added sugar. Due to the blueberries in this rhubarb berry crisp recipe, the sugar content can be lower. This blueberry rhubarb crisp is the perfect dessert to serve at a blueberry-themed party. Read on for one of the most delicious blueberry rhubarb recipes!

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Equipment for Easy Blueberry Rhubarb Crisp

1 8 by 8-inch baking pan (9 by 13-inch if you double the recipe) If you can find one with a lid, like the ones linked here, that helps with portability if you are going to a picnic or potluck.

1 medium-sized microwave-safe mixing bowl (This set is similar to what I have. Again, lids are nice.)

Ingredients for Easy Blueberry Rhubarb Crisp

2 cups blueberries, fresh or frozen

2 cups rhubarb, fresh or frozen

3/4 cup sugar

2 tablespoons flour

Topping

1/2 cup melted butter or margarine (I always use butter)

2/3 cup quick-cooking oatmeal

1/2 cup brown sugar

1/2 cup flour

1 tablespoon cinnamon

Directions for Easy Blueberry Rhubarb Crisp

Preheat the oven to 300 degrees. Rinse the blueberries in a colander and let drain. If you are using fresh rhubarb, rinse and slice the rhubarb stalks into bite-sized chunks. If you are using frozen rhubarb, the fruit should already be in chunks. In an 8-inch square baking dish, mix the blueberries and rhubarb with flour and sugar.

It’s okay if the blueberries and rhubarb are still a bit frozen. In a medium-sized microwave-safe mixing bowl, melt the butter or margarine in the microwave. Time will vary, depending on your microwave, but I usually set mine for 45 seconds. After the butter is melted, add the brown sugar, flour, oatmeal, and cinnamon to the bowl and mix. When the topping mixture is combined, distribute evenly over the top of the blueberries and rhubarb in the baking dish.

Bake the blueberry and rhubarb crisp in a 300-degree oven for 1 hour. This recipe makes 4 servings and may be doubled for a cake-size blueberry rhubarb crisp in a 9×13 baking dish. Serve warm with vanilla ice cream. Spectacular!

Other Names for this Amazing Blueberry Rhubarb Crisp Recipe

Have you ever heard the words blueberry and rhubarb put together to make blubarb? Some people call recipes with blueberries and rhubarb blubarb, as in blubarb jam. If you try typing it, the spellchecker or autocorrect will try to change it to blurb, but it really is a word all by itself. It’s not in the dictionary yet, but if enough people start using it, it soon will be. So, if you think saying blueberry rhubarb crisp is too much of a mouthful, try calling it blubarb crisp.

Some people also might call this a blueberry rhubarb cobbler. Since the crust gets crispy and crunchy, some might even call this recipe a blueberry rhubarb crumble. Whatever you prefer to call it, it’s one of the best rhubarb blueberry recipes around.

Gluten-Free Blueberry Rhubarb Crisp

You could easily adapt this blueberry rhubarb crisp recipe to make it gluten-free. Just use gluten-free measure-for-measure flour. I like the King Arthur brand, but there are other brands like Bob’s Red Mill and Krusteaz that work well also.

How do You Make a Sugar-Free Blueberry Rhubarb Crisp?

Can you cook rhubarb without sugar? If you are concerned about the sugar content and want to make the blueberry rhubarb crisp more healthy, try a sugar substitute. Once again, the King Arthur brand of plant-based keto-friendly sugar substitute for baking is a favorite. It’s also easy to find a sugar-free substitute for the brown sugar in the blueberry rhubarb crisp recipe as well.

Other Rhubarb or Blueberry Crisp Variations

If you would like to make a rhubarb crisp with frozen rhubarb, you could use 4 cups of rhubarb and omit the blueberries. Since rhubarb is so tart, you could increase the sugar to 1 cup, then toss it with the flour and rhubarb. In a similar way, if you would like to make blueberry crisp with frozen blueberries, just use 4 cups of blueberries and omit the rhubarb. You could keep the amount of added sugar to 3/4 cup as called for in the regular rhubarb and blueberry crisp recipe.

Tips for Cooking Rhubarb

If you have never cooked rhubarb before, you might have some questions. Sometimes, people might wonder, “Why is my rhubarb crisp runny?” The juices from rhubarb sometimes cause a rhubarb pie to be runny, and cornstarch can be used as a thickener. However, in this blueberry rhubarb crisp recipe, the flour acts as a thickener, and the crisp will thicken as it cools. The juices are part of what makes this recipe so delicious. The fruit juices will boil and bubble up around the edge of the topping as the blueberry rhubarb crisp bakes.

Should frozen rhubarb be thawed before baking?

In this rhubarb blueberry crisp recipe, it doesn’t matter if the rhubarb is thawed. If you feel the need to soften the fruit a little bit, you can just run warm water over it in a colander. This would be helpful if the pieces of frozen rhubarb are sticking together.

Should you Peel Rhubarb?

Are you supposed to peel rhubarb before cooking? Peeling rhubarb is not necessary for this recipe. Rhubarb doesn’t need to be peeled in the recipe for pineapple rhubarb jam either. It’s a very low-maintenance vegetable. (Yes, it’s a vegetable. I checked to be sure.) Should you peel rhubarb before freezing? That’s not necessary either. The only reason you might ever want to peel rhubarb is if the peel is quite stringy. That brings us to the next question.

Why is My Rhubarb Stringy?

The stalks on a rhubarb plant get stringy when the plant gets old and needs to be divided. If you have a friend who enjoys eating rhubarb, a rhubarb plant would make a great gift. Rhubarb is excellent for inspiring confidence in a novice gardener. We have had our rhubarb plant for years, have never divided it, and haven’t noticed excess stringiness. The recipes I use that call for rhubarb involve cooking the rhubarb pieces for quite a long time, so the rhubarb is quite soft by the time it gets eaten.

Do You Use the Whole Rhubarb Stalk?

The stalk is the only part of the plant that is edible. The leaves are not edible and should be discarded. Some rhubarb stalks are green, some are pink, and some are red. The color of the stalk doesn’t matter.

Does rhubarb crisp need to be refrigerated?

If there is any leftover blueberry rhubarb crisp, it is a good idea to refrigerate the leftovers. For those who like to eat their fruit crisp warm, just pop it in the microwave for 30 seconds. The best experience is to eat the crisp when it’s still warm from baking in the oven. It’s a good idea to let the crisp cool for a few minutes after baking, to let it firm up a bit.

Other Favorite Fruit Recipes

Do you have any favorite desserts or other recipes? What comes to mind when you think of delicious dessert dishes? I’m always intrigued to read the stories behind the recipes as well. What makes them so special? I’d love to read your recipe stories. Like the combination of rhubarb and blueberries together? Try making rhubarb blueberry coffee cake. If you have an abundance of apples, you might also like to make easy homemade applesauce. For a delicious beverage option, you could serve the rhubarb blueberry crisp with hot mulled cider (wassail). Enjoy making fruit desserts? You might like to try my recipes for easy oatmeal apple crisp, easy blueberry cobbler, or simple blueberry hand pies.

Is This Easy Blueberry Rhubarb Crisp Recipe Beckoning You?

Now you know how to make one of the simplest rhubarb and blueberry recipes. I’m going to make it for dessert sometime soon. The sweet deliciousness is calling my name. Has this recipe made you want to rush outdoors to pick blueberries and rhubarb? Or rush to your freezer and raid your frozen blueberry and rhubarb stash? If you decide to try it, I’d love to know what you like to serve it with. Did you take it to a gathering and receive rave reviews?

More Food Inspiration

Whether you are making a treat or making a meal, it’s always nice to have a plan. If you’re looking for a way to get more organized with your food planning efforts, I’ve got something for you. Free, editable meal planners! The templates can be used over and over, as often as you need them. You can make as many duplicates as you like, and you’ll be able to save old meal plans for future reference. I hope it simplifies things for you.

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If you would like even more recipe ideas, consider following my Easy Recipes board on Pinterest. Have a fabulous day, and I hope you get to enjoy this easy blueberry rhubarb crisp recipe.

Lisa Mitchell is a wife, mom, and school librarian who likes to create and share recipes, often using fresh ingredients from her family’s small Pacific Northwest farm. To learn more about what this website has to offer, click on over to the Food page.

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