Easy Blackberry Oat Squares with a Buttery Shortbread Base

These blackberry oat squares combine buttery shortbread, juicy blackberries and an oaty custard might sound a little unexpected, but trust me—it works beautifully. The shortbread base brings a satisfying crunch, while the blackberries offer that perfect balance of tartness and sweetness, bursting with natural flavour. Then come the oats, grounding the whole bake with a gentle nuttiness and an earthy depth that ties everything together.

Crunchy Shortbread

I have a delicious shortbread recipe here on the blog that you should definitely check out. In fact, in that post I delve a little deeper into what makes perfect shortbread and how you can achieve the same results in your own kitchen.

This recipe for the blackberry oat squares though is a little different and not as involved. The key points we will take away include oven temperature and cook time. Also take note of your butter we need it to be at room temperature.

If you are interested and would like to check out my shortbread recipe, just click on the image below.

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Making Blackberry Oat Squares

Tools

• Mixing bowl
• Spatula
• Measuring spoons
• Kitchen scale or measuring cups
• Electric beater or a stand mixer with the paddle attachment
• 9×9 Baking tin
• Parchment paper

Ingredients

• All purpose plain flour
• Salted butter
• Granulated sugar
• Blackberries
• Lemon juice
• Vanilla Extract
• Oat flour, you can grind your own with rolled oats using a blender
• Rolled oats, these are not the same as quick oats
• Large eggs

How to make Blackberry Oat Squares

Shortbread base

We are starting from the bottom up in this recipe. First the shortbread base, we will begin by placing the flour and butter into a mixing bowl.

You can either do this step by hand or you can use a stand mixer with the paddle attachment. Rub the butter into the flour until it starts to resemble breadcrumbs.

Add in the sugar and mix it in well you can still use your hands to do this.

Work the mixture now until a dough ball forms. Again this can be achieved using your hands, or you can use an electric mixer.

Line a 9×9 baking tin with some parchment paper, this will allow you to remove the bake from the tin easily. I like to grease the tin lightly so that the parchment will stick and hold in place. Making it easier when you add the filling.

Tip the shortbread dough into the baking tin and press it down evenly, so that it fill the base. Then using a fork prick some holes throughout.

Place the shortbread into a preheated oven and bake.

Fruit Filling

While the shortbread is cooking we will move onto the next step. The blackberry fruit filling.

Into a small saucepan, add all of the ingredients, including the blackberries, sugar, and lemon juice. However, if you are using frozen berries, they will need to be defrosted beforehand, with some of the excess juices drained.

Using a fork mash the fruit down to a pulp, place this pulp and slowly bring to the boil. When the fruit starts to thicken very slightly remove the pot from the heat and place it to the side until we need it. Now lets move onto the topping.

The Oat topping

Into a mixing bowl (you can use the same bowl you used for the shortbread base, you don’t even need to wash it) add the butter and sugar, beat these ingredients together.

Once they begin to look a little like mashed potatoes add the eggs one at a time beating them gently in between. This step will be the easiest if you have an electric beater. nest add the vanilla extract.

When they are combined add in the oat flour and oats and give it one last mix.

Now to assemble.

Assembling and Baking the Blackberry Oat Squares.

By this point your base should either be ready or nearly ready once it is baked it is time to assemble and do the final bake.

Take the fruit and pour it over the shortbread and spread it out evenly, making sure to get it right to the edges.

Next, carefully spoon over the oat mixture again making sure it covers the top completely.

Place the baking tin into the oven and bake. When the topping no longer jiggles and has set, remove from the oven and leave it to cool completely before removing the blackberry oat bake from the tin.

Once completely cooled carefully lift the bake out of the baking tin, placing it onto a cutting board. Cut evenly into squares you should get a minimum of twelve blackberry oat squares out of the recipe.

Tips for Blackberry Oat Squares

• Make sure your butter for the shortbread is close to room temperature. It still should hold its shape and be slightly firm to the touch.
• You can use frozen fruit for this recipe in fact it is a perfect recipe for frozen but they will need to be defrosted and drained first.
• Make sure you do not over cook the fruit, you want to retain some of the juice.
• If you are using a stand mixer it is always worthwhile scraping the mixing bowl between each step. For both the base and the topping.
• You can male your own oat flour all you need is a blender and some extra rolled oats. Blend the oats until they resemble a flour like texture.