Delicious Blueberry Sheet Cake

This blueberry sheet cake is the perfect balance of light, fluffy sponge and juicy berries The simple batter comes together quickly, creating a lovely cake with bursts of sweet-tart blueberries. Whether served as a casual afternoon tea treat or dressed up for a special occasion, this versatile cake is sure to become a family favourite.

Ingredients You’ll Need

• Fresh or frozen blueberries
• Plain flour
• Baking powder
• Butter
• Caster sugar
• Eggs
• Vanilla extract
• Milk or buttermilk
• Lemon zest
• Icing sugar

See the recipe card for quantities.

Instructions

Follow these simple steps to create a perfectly baked blueberry sheet cake that's moist, tender, and bursting with berry goodness.

1. Step 1: Preheat your oven to 175°C and prepare your 9x13-inch baking pan with grease or parchment paper.
2. Step 2: Cream together the softened butter and caster sugar until light and fluffy, about 2-3 minutes.
3. Step 3: Add the eggs one at a time, beating well after each addition, followed by the vanilla extract and lemon zest (if using).
4. Step 4: In a separate bowl, whisk together the flour and baking powder.
5. Step 5: Alternately add the dry ingredients and milk to the butter mixture, beginning and ending with the dry ingredients.
6. Step 6: Gently fold in the blueberries until evenly distributed throughout the batter.
7. Step 7: Pour the batter into the prepared baking pan and spread it out evenly.
8. Step 8: Bake for 30-35 minutes, until golden on top and a toothpick inserted into the centre comes out clean.
9. Step 9: Allow the cake to cool before dusting it with icing sugar, if desired.

Hint: When using frozen blueberries, don't thaw them before adding to the batter. Add them frozen to prevent the colour from bleeding too much into the cake batter.

Substitutions

• Flour: use a measure-for-measure gluten-free flour blend instead of plain flour to make this cake gluten-free
• Butter: substitute with a plant-based butter and use plant milk to make this cake dairy-free
• Sugar: replace caster sugar with coconut sugar for a healthier version, though this may darken the cake colour slightly

Variations

• Mixed Berry: Replace half the blueberries with raspberries or blackberries for a colourful mixed berry cake
• Lemon Drizzle: After baking, drizzle the warm cake with a simple lemon glaze made from lemon juice and icing sugar
• Almond: add ½ teaspoon of almond extract and sprinkle sliced almonds on top before baking for a nutty twist

Equipment

A 9x13-inch (roughly 23x33 cm) metal baking tin is ideal for this recipe. If you use a glass baking dish instead, reduce the oven temperature by about 10°C and be prepared to extend the baking time slightly, as glass heats more slowly but retains heat longer than metal.

An electric mixer (stand or handheld) makes the creaming process much easier, but a wooden spoon will work perfectly fine if you don't have one.

Storage

This blueberry sheet cake stays moist and delicious when stored in an airtight container at room temperature for up to 2 days. For longer storage, keep it in the refrigerator, where it will remain fresh for up to 5 days.

This cake freezes beautifully. Cut it into individual portions, wrap each piece in cling film, and store it in a freezer bag or container. The cake will keep in the freezer for up to 3 months. Thaw pieces at room temperature or warm slightly in the microwave before serving.

Top Tip

For the most even distribution of blueberries, toss your berries in a tablespoon of the flour mixture before folding them into the batter. This helps prevent them from sinking to the bottom during baking.

Pairing

These are my favourite accompaniments to serve with this blueberry sheet cake:

• A dollop of lightly whipped cream for a simple but elegant dessert
• Vanilla ice cream for a more indulgent treat
• A cup of Earl Grey tea or coffee for afternoon tea

📖 Recipe

Blueberry Sheet Cake

These blueberry cake squares are a delightful treat that is light, moist, and bursting with fresh berry flavour.

Print Recipe Pin Recipe

Prep TimePrep Time 25 minutes minutes

Cook TimeCook Time 35 minutes minutes

ServingsServings 12

Equipment

• 9x13-inch baking pan (for thinner squares, or use a smaller pan for thicker squares)
• Mixing bowls
• Electric mixer (optional, but helpful for creaming butter and sugar)
• Spatula and whisk

Ingredients  

• 250 g fresh or frozen blueberries
• 240 g plain flour
• 1 ½ teaspoons baking powder
• 115 g butter softened
• 200 g caster sugar
• 2 large eggs
• 1 teaspoon vanilla extract
• 120 ml milk or buttermilk for extra tenderness
• 1 teaspoon lemon zest optional, for brightness
• Powdered sugar optional, for dusting

Instructions 

• Preheat your oven to 175°C and grease or line your 9x13-inch baking pan with parchment paper for easy removal.
• In a large mixing bowl, cream together the softened butter and granulated sugar until light and fluffy, about 2-3 minutes. You can do this by hand, but an electric mixer makes it much quicker.
• Add the eggs one at a time, beating well after each addition, followed by the vanilla extract and lemon zest (if using). The lemon zest adds a bright citrus note that pairs beautifully with the blueberries, but it’s completely optional.
• In a separate bowl, whisk together the flour and baking powder. Add half of the dry ingredients to the wet mixture, followed by half of the milk. Mix until just combined, then repeat with the remaining flour and milk. Be careful not to overmix—just stir until the batter is smooth.
• Finally, gently fold in the blueberries, making sure they’re evenly distributed throughout the batter.
• Pour the batter into the prepared baking pan, spreading it out evenly with a spatula. Bake in the preheated oven for 30-35 minutes, or until the top is golden and a toothpick inserted into the center comes out clean.
• If you’re using a smaller pan for thicker squares, the baking time may increase by about 5-10 minutes. Just keep an eye on it to avoid overbaking.
• Allow the cake to cool in the pan for 10-15 minutes before transferring it to a wire rack to cool completely. Once cooled, slice the cake into squares of your desired size.
• For an extra touch, dust the top of the cake squares with powdered sugar before serving. The light dusting gives them a bakery-style finish that makes them look as good as they taste!

Notes

• Lemon Flavour: Want to take the citrus flavour up a notch? Add a tablespoon of fresh lemon juice to the batter along with the zest for a delicious blueberry lemon twist.
• Glaze Topping: If you love a little extra sweetness, drizzle a simple lemon glaze over the top. Just mix 1 cup powdered sugar with 1-2 tablespoons of lemon juice and drizzle it over the cooled cake.
• Other Berries: Feel free to substitute the blueberries with other berries like raspberries, blackberries, or even a mix of berries for a different flavour.
• Vegan Version: Use plant-based butter, almond or oat milk, and a flax egg substitute (1 tablespoon ground flax mixed with 3 tablespoons water per egg) for a vegan-friendly version.