Walnut-Oat Apple Crumble

Walnut-oat apple crumble is a rustic comforting dessert of caramelized apples laced with cinnamon under a sweet crumble crust of hearty oats and toasted walnuts.

Apple Crumble a Timeless Classic | Our Lady of Second Helpings

An apple a day may keep a doctor away, but I bet they would come running if you put that apple into this crumble!

I have been working my way through 80 pounds of apples. There was a full weekend of simmering that resulted in many quart and pint jars filled with apple-ginger, apple-cardamom, and apple-cinnamon sauces. Later in the week three pounds of large green tomatoes paired with three pounds apples to make 5 pints of Green Tomato and Apple Chutney using a recipe posted by Hannah at Blue Kale Road. A few days after that I filled my soup pot with 8 quarts of chopped apple and a bit of rhubarb to make 17 half pints of rhubarb and apple jam. To make the jam I did a riff on the honey-lemon-apple jam I made last year from Food in Jars recipe.

In case you are thinking about attempting this combo it was approximately:

  • 8 qts of chopped fruit, (about 7 to 1 apples to rhubarb and around 1/3 Granny Smith apples) and 1 1/2 cups of fresh lemon juice simmered until saucy.
  • Add 2 cups of honey and 4 cups of sugar and boil until jammy.


One by one I ladled all those spicy, sweet, and sour apple concoctions into jars and sealed them in a vat of boiling water. Eventually, I was out of jars and out of energy – but not out of apples. I also hadn’t eaten many apples. So I went back to the drawing board with one of my favorite fruit desserts.

I have made countless crumbles. It is a go-to dessert suitable for most varieties of fruit. As much as I like the simplicity of a crumble I feel that each combination of fruit requires a slightly different approach. Finding the perfect recipe for all of my favorite crumble fruits is a labor of love I am happy to undertake.


When it comes to apple crumbles this updated recipe is my current favorite. It is the dessert equivalent of my most well-worn cable knit sweater. Aside from apples and cinnamon, I feel, the key ingredient in this recipe is tapioca starch. Where most recipes call for tossing the chopped fruit with all purpose flour I have begun using tapioca flour. This change came after a tip from Kate McDermott, of Art of the Pie. She recommends using tapioca flour, also called tapioca starch, in pie fillings and after I saw how well it worked in pie filling I have been trying it in other desserts. What I love about the starch is the way it absorbs fruit juice creating a thick but not gelatinous syrup that coats the fruit rather than separating into a puddle at the bottom of the dish. Tapioca flour has none of the grainy texture or pasty flavor that can result from using wheat flour and you can use less with a much more attractive result. I have found tapioca flour, packaged by Bob’s Red Mill, on the shelf at Whole Foods and, online, at Amazon.

Whether you are looking to attract or repel a physician, cook your way through 80 pounds of apples, or make a timeless dessert to share with friends, I hope you’ll put this apple crumble on your fall menu.

Apple Crumble a Timeless Classic | Our Lady of Second Helpings

Apple Crumble a Timeless Classic | Our Lady of Second Helpings

Walnut-Oat Apple Crumble
Prep time
Cook time
Total time
Walnut-oat apple crumble is a rustic comforting dessert of caramelized apples laced with cinnamon under a sweet crumble crust of hearty oats and toasted walnuts.
Recipe type: Dessert
  • Base
  • 3 lbs of apples assorted variety (approximately 6 large) recommend using at least 2 Granny Smith
  • 2½ tablespoons tapioca starch (also called tapioca flour)
  • 3 tablespoons brown sugar (dark brown preferred)
  • ½ teaspoon ground cinnamon
  • Crumble Topping
  • ½ cup rolled oats (not quick cook)
  • ⅓ cup all-purpose flour*
  • ½ teaspoon ground cinnamon
  • ½ teaspoon ground nutmeg
  • ⅛ teaspoon salt
  • 3 tablespoons cold butter, unsalted
  • ¼ cup of walnut halves, minced
  1. Preheat the oven to 400 degrees and have a 2½ – 3-quart casserole or 13×9 baking dish standing by.
  2. Peel, core, and chop the apples into medium size pieces (approximately ¾ inch thick and 1½ – 2 inches long). Then toss the apple pieces with the tapioca starch, brown sugar, and cinnamon. Turn the coated apples into the waiting baking dish.
  3. Measure the oats, flour, cinnamon, nutmeg, and sugar into a medium mixing bowl and give them a couple stirs with a fork to combine. Cut the butter into small pieces and use your fingers to work the butter into the flour mixture. Working as quickly as possible to keep it cold, crumble the butter and flour together until the butter is broken into tiny pieces no bigger than a small pea. Stir the minced walnuts into the flour and butter mixture then sprinkle the topping over the apples in an even layer.
  4. Place the dish in the preheated oven and bake for 40-45 minutes until the apple juices are caramel colored and bubbly.
  5. Allow the crumble to cool for an hour or more before serving the juices will thicken as they cool wrapping the apples in a cinnamon-infused caramel-like syrup worth waiting for.
Brown rice flour will work in place of all-purpose flour to make this crumble gluten-free, this may alter the nutrition information.
Nutrition Information
Calories: 209 Fat: 7g Carbohydrates: 36g Fiber: 4g Protein: 2g



  1. What a lovely apple crumble, Rose! Wow, you’ve been busy with apples (I’m delighted you made the green tomato and apple chutney!) and you’re inspiring me. I’ve been buying cases of apples from the local orchards here and am looking for more ways to use/preserve them – so far it’s been many varieties of applesauce. Thanks for all your ideas you share! I hope you and your family are doing well and enjoying a beautiful fall.

    • Oh I bet you are having a marvelous time surrounded by orchards. It is hard to go wrong with applesauce! Have you added anything besides apples to yours?

      The chutney turned out great I was so glad to find your recipe. Thank YOU for all of your ideas!

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