Blueberry Oat Crumb Bars

Featured in Treats That Make Everything Better.

Oat bars with a fruity center and crumbly top. Done in about 70 minutes, yields 12 tasty squares.
Clare Recipes
Updated on Mon, 28 Apr 2025 20:59:30 GMT
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Blueberry Oat Crumb Bars Made with Whole Ingredients | recipesclare.com

There's a touch of wonder when you take these fruit-packed squares out from the oven, seeing the blueberries simmering and hearing the oat topping snap as it gets cold. I came across this idea when blueberry harvest hit and my kitchen counters couldn't hold any more fresh-picked fruit while my children got bored with plain oatmeal each morning.

These squares saved our family camping adventure last year when downpours kept us stuck in our tent. My kids still chat about how we all cuddled up, munching on these treats with warm cocoa while the storm passed by.

Key Components

  • Old-Fashioned Oats: They give you that wonderful substantial bite
  • Plump Blueberries: Sweet little gems that pop with juicy flavor
  • Rich Brown Sugar: Brings a lovely molasses warmth to every bite
  • Touch of Cinnamon: Just a hint to lift all the other flavors
  • Pinch of Sea Salt: Cuts through sweetness for the perfect taste
  • Quality Butter: Don't skimp here - it really shows in the final product
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Breakfast Blueberry Oatmeal Crumb Bars Recipe | recipesclare.com

Step-by-Step Method

Setting Up:
Cover your baking dish with foil to make a snug spot for your treats
Mix It Up:
Combine all your dry stuff until everything's properly mixed
Butter Transformation:
Add your melted butter and watch the mixture come together
Bottom Layer:
Push half your mix firmly into the pan with care
Fruit Addition:
Sprinkle your juicy blueberries across like little blue treasures
Top It Off:
Scatter remaining mixture over berries for that signature crunch
Bake With Care:
Let your kitchen fill with amazing smells as they turn golden brown
Wait It Out:
Now comes the tough part - letting them cool all the way through

My high schooler now whips these up by herself every Sunday, saying it helps her unwind before Monday comes around. The kitchen ends up looking like a disaster zone, but watching her smile when they come out just right makes the cleanup worth it.

Morning Game-Changer

We've started taking these squares on "sunrise picnics," packing them with hot drinks for early walks by the ocean. Something about fresh sea breeze makes them taste twice as good.

Fruit Swaps

Once blueberries go out of season, we try other fruits instead. Raspberries add a pink color and tangy kick, blackberries make them dark and rich, while using several berries together creates pretty swirls throughout.

Keeping Fresh

These hardy squares have shown up in packed lunches, survived long car trips, and even made it on a plane to give my mother a tasty surprise. They hold together really well once they've cooled properly.

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Blueberry Oatmeal Crumb Bars Recipe | recipesclare.com

Breakfast Traditions

The aroma of these baking has turned into our family's end-of-weekend signal - Sunday might be over, but at least we've got something yummy waiting for us Monday.

After making batch after batch, these squares have grown beyond just breakfast food - they've turned into our weekend ritual, lunchbox treat, and afternoon snack all wrapped up in one tasty package. They've shown me that basic recipes often create the longest-lasting memories.

Frequently Asked Questions

→ What type of oats works best?
Go for old-fashioned oats or thick flakes. Avoid quick oats—they won’t turn out right.
→ Can frozen berries be used?
Absolutely! Just extend the baking by 10-15 extra minutes.
→ Why wait to slice them?
They slice much better after cooling for at least 3 hours.
→ Best way to store these?
Once cooled, keep them in an airtight container. Refrigerate to store them longer.
→ Are these recipes paleo-friendly?
These have oats and flour, so they’re not paleo. Swap flours to make it paleo-friendly.

Blueberry Oat Crumb Bars

Crispy-bottom oat bars stuffed with juicy blueberry filling and a crumbly top layer. They're wholesome and perfect to grab in the morning or snack later.

Prep Time
20 Minutes
Cook Time
50 Minutes
Total Time
70 Minutes

Category: Sweet Stuff

Difficulty: Intermediate

Cuisine: American

Yield: 12 Servings (12 squares)

Dietary: Vegetarian

Ingredients

→ Crumble & Base

01 1 large egg yolk
02 1/4 cup dark brown sugar
03 1/4 teaspoon sea salt
04 1/2 cup melted unsalted butter
05 3/4 cup old-fashioned oats
06 1/2 teaspoon powdered cinnamon
07 1 tablespoon extra dark brown sugar
08 1 cup all-purpose flour
09 1/2 cup granulated sugar

→ Berry Layer

10 1/4 cup granulated sugar
11 2 teaspoons starch (cornstarch)
12 2 cups blueberries (use fresh or thawed frozen ones)
13 2 tablespoons fresh-squeezed lemon juice

Instructions

Step 01

Set your oven to 350°F and let it preheat. Use butter to grease an 8x8 pan that's been lined with foil.

Step 02

Combine the oats, sugars, salt, flour, and cinnamon. Stir in egg yolk and melted butter.

Step 03

Set aside 1 cup of the mixture to use later. Push the rest firmly down into the pan you prepped.

Step 04

Combine blueberries, cornstarch, sugar, and lemon juice in a bowl. Spread it evenly over the crust base.

Step 05

Sprinkle a little extra brown sugar into the reserved mix. Then crumble it all over the blueberries.

Step 06

Bake until the edges are golden and the topping looks bubbly, about 40-45 minutes. Let it cool completely (at least 3 hours) before slicing.

Notes

  1. Skip quick or instant oats for this recipe
  2. Frozen blueberries take 10-15 extra minutes
  3. For easy cutting, wait until it's fully cool

Tools You'll Need

  • Square baking pan (8x8 inches)
  • Foil for lining the pan
  • Mixing bowls

Allergy Information

Please check ingredients for potential allergens and consult a health professional if in doubt.
  • Made with dairy (butter included)
  • Contains eggs
  • Gluten is in the flour

Nutrition Facts (Per Serving)

It is important to consider this information as approximate and not to use it as definitive health advice.
  • Calories: 188
  • Total Fat: 6.21 g
  • Total Carbohydrate: 33.39 g
  • Protein: 2.98 g