Lemon Blueberry Cake

The Cake I Make Every April (Whether Anyone Asks For It or Not)
This lemon blueberry cake is moist, tender, and loaded with juicy blueberries — then topped with a tangy cream cheese frosting with just a hint of lemon. It’s a simple recipe that works beautifully as an easy 9×13 sheet cake or a showstopping layer cake, and it always gets rave reviews.

Why You’ll Love It

Moist, tender crumb — no dry slices, every bite is soft and delicate
Bright lemon flavor — from both the zest and fresh juice, not the bottled stuff
Juicy blueberries throughout — they get jammy as they bake and every bite has one
Tangy cream cheese frosting — not too sweet, with just enough lemon to complement the cake
Two ways to make it — easy sheet cake or an impressive layer cake, same batter either way

A Few Notes on the Ingredients

Use cake flour. I know not everyone keeps it around — I didn’t for years — but it makes a real difference here. The crumb is softer, more delicate, and it doesn’t go dense the way all-purpose can in a recipe like this. If you’re truly out of it, there’s a substitute in the notes (all-purpose plus cornstarch), but if you have any advance warning that you’re making this, just pick up cake flour. It’s worth it.
The buttermilk is non-negotiable in my opinion. I’ve used regular whole milk in a pinch and it’s fine — it’s fine — but it’s not the same. Buttermilk does something to the texture that I couldn’t explain scientifically if you paid me, but you can taste it. Just use the buttermilk.
Fresh lemons. Not the plastic lemon-shaped thing in the refrigerated section. Real lemons, zested first (always zest before you cut them — I’ve made that mistake), then squeezed. You’ll need about three good-sized ones.
For the blueberries — fresh, if you can. I’ve used frozen when I was desperate and the cake was still good, but they do sink a little and they bleed a bluish-purple color into the batter in a way that’s a little less pretty. Not the end of the world. But fresh is better.
And for the cream cheese, please use full-fat brick-style. Not the whipped stuff. Not the reduced fat. The brick.

Ingredients

For the Cake:

3 cups cake flour (360g)
2 teaspoons baking powder
½ teaspoon baking soda
½ teaspoon salt
¾ cup buttermilk, room temperature — and actually let it come to room temp, don’t skip this
⅓ cup fresh lemon juice (about 80ml)
1 cup unsalted butter (226g), softened
1¾ cups granulated sugar
2 tablespoons lemon zest
2 teaspoons vanilla extract
4 large eggs, room temperature
2 cups fresh blueberries
2 teaspoons cake flour, for tossing the berries

For the Cream Cheese Frosting:

¾ cup unsalted butter (168g), softened
12 oz full-fat brick-style cream cheese (340g)
1½ teaspoons fresh lemon juice
4½ to 5½ cups powdered sugar, sifted — start with less and add more
1 to 2 tablespoons whipping cream, as needed

Instructions

Preheat your oven to 350°F. For a 9×13 pan, grease and flour it and you’re basically done with prep. For the layer cake, line the bottoms of your round pans with parchment rounds — actually line them, don’t skip it, I speak from experience — and then grease and flour the sides.
Sift your dry ingredients together first. Cake flour is lumpy and sifting matters here. Whisk them together after.
In a small bowl or measuring cup, combine the buttermilk and lemon juice. It’ll look a little weird, slightly curdled maybe — that’s fine. Set it aside.
Cream the butter with the sugar and lemon zest in a big bowl. You want it fluffy and lightened, a couple of minutes at least. Add the vanilla, then add the eggs one at a time, scraping down the bowl after each one. Don’t rush this part.
Now — alternate adding the flour mixture and the buttermilk mixture, starting and ending with flour. About a third of the flour, half the liquid, another third of flour, the rest of the liquid, then the last of the flour. Do the last few stirs by hand with a spatula. Don’t overmix. This is where I always have to remind myself to slow down — I get impatient and I’ve ended up with tough cake before by rushing this step.
Toss your blueberries with those two teaspoons of flour in a small bowl. Then fold them into the batter gently. Very gently. You’re not stirring, you’re just sort of… nudging them in.
Pour into your prepared pans. For a 9×13, bake about 30–35 minutes. For three 8-inch rounds, closer to 25–30. Test with a toothpick — it should come out clean, or with just a few moist crumbs.
Let the cakes cool completely in the pan. If you’re making layers, wait until they’re totally cold before you try to turn them out — I lost a cake layer once trying to rush this and I’m still not over it.
Frosting: Beat the softened butter and cream cheese together until smooth. Add the lemon juice, then the powdered sugar gradually. Add whipping cream if it’s too stiff. You want it spreadable but not loose.
If you’re doing a layer cake, get the cake layers cold first — I usually wrap them in plastic and refrigerate overnight. Trim the domed tops off if needed. Stack with about ¾ cup frosting between each layer, do a thin crumb coat on the outside, refrigerate for 30 minutes, then do your final layer of frosting. Top with extra blueberries if you have them.

Variations

This works beautifully with raspberries instead of blueberries — different berry, same technique, equally delicious.
You can also skip the layer cake entirely and just do the sheet pan version, which I mentioned but I’ll say again — the cake is the same. Some people prefer it, actually. Less fuss, more cake.

Storage

The frosted cake will keep in the fridge, covered, for about four days. It’s best the day it’s made — the berries can make it a little wet after a couple of days, though it’s still good. Unfrosted layers can be wrapped tight and frozen for up to two months, which is useful if you want to make this in stages.