Moist Blueberry Cake with Lemon Glaze

Can I use Frozen Blueberries in this Blueberry Cake?

Yes! Regular frozen blueberries work great, as do wild frozen blueberries.

Should I Thaw Frozen Blueberries Before Adding Them?

No, you do not need to thaw frozen blueberries before adding them to your cake batter.

If they defrost, the excess liquid will streak and color your cake batter purple!

Will The Blueberries Sink?

Nope! The blueberries sit comfortably throughout this cake without sinking to the bottom.

The reason? This blueberry cake is not as tall as regular round cakes, as it’s baked in a sheet pan.

Therefore the blueberries hover around the middle of the cake crumb during baking.

There is no need to toss the blueberries in flour beforehand, I kind of believe that’s a myth!

Ingredient Notes & Substitutions

A comprehensive recipe card featuring all the ingredients can be found at the end of this post.

• All-purpose flour: Also known as plain flour in Australia. Make sure to accurately measure your flour for the best results.

• Baking powder and baking soda: Ensure these are not expired. It’s easy to test if your leavers are still active.

• Granulated sugar: I used golden/raw granulated sugar for its added flavor. You can substitute it with regular white granulated sugar.

• Salt: Any fine salt will do.

• Egg: Must be at room temperature and lightly beaten before adding.

• Whole milk: Full-fat milk produces the best and most moist results. Can be substituted with low-fat milk or a dairy-free milk such as almond milk.

• Olive oil: Extra virgin olive oil works best. Alternatively, use neutral-flavored vegetable oil as a substitute.

• Vanilla extract: Can be substituted with one teaspoon of vanilla paste.

• Blueberries: You can use either frozen or fresh blueberries in this cake. If using frozen, add them directly from the freezer into the batter—no thawing needed. Wild blueberries may also be used.

• Unsalted butter: Use butter that comes in a block. Can be substituted with salted butter.

• Lemon juice: For best results, use freshly squeezed lemon juice.

• Powdered sugar: Also known as icing or confectioners sugar.

Step By Step Instructions (with photos)

There is a full and detailed recipe card at the bottom of this post.

Step one: Preheat oven to 180ºC (356ºF) fan-forced.

Step two: Line with parchment paper a 7-inch x 11-inch (17cm x 27cm) rectangle/sheet cake tin.

If you have a non-stick pan and want a smooth-sided cake, line the base of the tin with parchment while greasing the sides with butter and adding a light dusting of flour to the butter. Tapping out the excess flour.

Step three: In a large mixing bowl, whisk together flour, baking powder, baking soda, sugar, and salt until well combined.

Step four: Add the beaten egg, milk, oil and vanilla to the dry ingredients.

Gently fold with a rubber spatula until incorporated and no streaks of flour remain. Do not overmix.

Step five: Fold in the blueberries, being careful not to overmix.

Step six: Pour the batter into the tin and smooth the top with a spatula.

Step seven: Bake for 28-30 minutes or until lightly golden on top and a toothpick inserted into the middle comes out clean. 

Step eight: Remove from the oven and don’t remove the cake from the tin yet! Set it aside as you’ll now immediately make the lemon glaze to pour over the warm cake. 

Step nine: In a small saucepan, combine butter and lemon juice over low heat. Stir until butter melts.

Step ten: Add powdered sugar and vigorously whisk until smooth and thick.

Step eleven: Pour the warm icing over the warm cake still in the tin, spreading it with a spatula.

It will settle around the edges, and that’s okay, it will all soak through the cake and down the sides.

Allow the cake to cool completely in the tin and for the icing to set.

Scroll down to see what the cake tin looks like fully lined with the parchment paper. It’s easy to lift the cake out.

Here is what the cake looks like just greased with butter and flour (the base is lined) on the left.

On the right is the cake tin fully lined with parchment paper, it’s easy to lift the cake out this way.

Step twelve: Once cooled, lift the cake out by the parchment and place it on a wire rack or board.

Carefully peel off the parchment. Use a slotted turner; handle the delicate cake carefully.

If you greased/floured the sides, carefully invert the cake onto one wire rack/board, then immediately flip it right-side up onto a second wire rack.

Serve and enjoy!

Expert Tips

• Measure your baking ingredients accurately: Check out my helpful guide on how to measure basic ingredients.

• Lining cake tin: For hassle-free cake removal, especially after adding the lemon glaze over the cake still in the tin, you have two good options:

1. The first is to line the entire cake tin with parchment paper, which makes lifting out the cooled and set cake a breeze. 
2. The second approach is to only line the base of the tin with parchment while greasing the sides with butter and adding a light dusting of flour. This method works well with a non-stick tin. 

With either approach, it’s crucial to wait until the icing has fully set before flipping the cake out of the tin and onto a wire rack.

• Do not over-mix the cake batter: It will result in a tough and dense textured cake after baking. 

• How to check the cake is baked: Test the cake’s doneness by inserting a toothpick into the center. If it’s clean or has a few crumbs, you’re good to go!

Storage Instructions

Store: Once cooled, store your cake in an airtight container, at room temperature, for 2-3 days.

Then, transfer to the refrigerator for a further 1-2 days to keep fresh as it contains blueberries and has a moist texture.

Keep in mind the texture will firm up while in the fridge, but it keeps the cake fresher for longer. Allow it to sit at room temperature for 15-30 minutes before enjoying.

How To Freeze

1. Freeze the cake either in individual slices or as a whole cake, with or without the lemon glaze.
2. Wrap the whole cake/slices tightly in either plastic wrap or a sheet of parchment paper.
3. Then, wrap it again in tin foil for added protection.
4. Label the wrapped cake with the date of freezing for easy reference.
5. Store the cake in the freezer for up to 2-3 months.

How To Thaw

If you’ve frozen the cake without the lemon glaze, you can add the glaze after thawing. However, be aware that the glaze will sit on top rather than soaking in, as the cake is no longer warm.

Refrigerator Thawing:

This gradual thawing process helps retain the cake’s moisture and texture.

1. Remove the wrapped cake from the freezer.
2. Place the cake in the refrigerator, keeping it completely wrapped.
3. Let the cake thaw slowly for several hours or overnight.

Room Temperature Thawing:

This quick thawing method ensures the cake softens fast.

1. Keep the cake wrapped in plastic wrap and tin foil.
2. Let it sit at room temperature for a few hours until softened.
3. Avoid direct sunlight or heat exposure during thawing.

Partial Thawing for Slicing:

If you froze the entire cake but want only one or a few slices, this process allows you to enjoy individual slices while keeping the rest fresh for later.

1. Remove the cake from the freezer and let it sit at room temperature for about 30 minutes to an hour.
2. Allow it to partially thaw until it softens enough to be easily sliced.
3. Slice the desired portions.
4. Refreeze any remaining cake portions you don’t plan to serve immediately.