Bright lemon flavor with a tender, fluffy crumb meets triple lemon buttercream, lemon curd mascarpone filling, and extra lemon curd for good measure. This lemon & mascarpone cake is a wonderful balance of lemon and creamy and sweet. Lemon lovers—you’ve finally found a cake that’s actually lemony enough, while still being delicious and sharable with everyone—even chocolate lovers!

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How was your long weekend? Or did you get a long weekend? My husband doesn’t get yesterday off, so he had to suffer through trying to WFH while I entertained our daughter inside all day, because rain. I tried to have her help me make a cake…but I forgot I’d planned an Irish Coffee Cake for this weekend (coming soon for St. Patty’s Day!) and it’s not so easy to have a toddler help make a boozy cake. They have this habit of getting frosting on their hands and immediately licking it off. Yeah, not so great when it’s Irish coffee buttercream.

But I have had the time to practice my photography this weekend, and those sneaky little frosting-stealing hands were one of my test subjects. Look at those tiny fingers!

Is there anything cuter than toddler fingers???

One thing those little hands were able to help me with was this lemon cake. We made it for her YiaYia’s birthday party and she was so proud to help.

This cake is so delicious but definitely for lemon lovers. I crammed as much lemon in it as I could, including infusing the milk with lemon zest. Where the flavor really comes out is the frosting and filling, so you can easily tone down the lemon if you want just a hint.

I think the filling is my favorite. The mascarpone and lemon curd complement each other beautifully. It does require more refrigeration during the frosting process, but once you get that crumb coat on and chilled, you’re set and it will hold up nicely.

How to make lemon & mascarpone cake

First, make your lemon curd (if using homemade).

Stir together the milk and lemon juice and set aside while you prep the rest of the ingredients. It will turn into buttermilk while you make everything else.

Sift and whisk together cake flour, baking powder, and salt. Set aside.

In a food processor or blender, pulse the sugar and lemon zest, until well blended and no large chunks of zest remain. It should slightly resemble wet sand.

Beat the butter on high until smooth. Add the lemon sugar and beat on high until light and fluffy.

Add the eggs, one at a time. Add the oil and vanilla.

Add half the flour, then the lemon milk, then the rest of the flour, beating on low until just barely combined after each addition.

Divide evenly between prepared pans. Bake until a toothpick inserted in the middle comes out with a few moist crumbs.

While the cakes cool, make the triple lemon buttercream.

Make the mascarpone filling. Gently stir the mascarpone with a rubber spatula until smooth. Add the powdered sugar and lemon curd and stir until smooth.

Fill with a thin layer of buttercream, the lemon curd mascarpone and a thin layer of plain lemon curd (optional). Frost with a crumb coat and chill (non-negotiable—it will slide off if the mascarpone isn’t re-chilled). Frost to desired thickness and enjoy!

Chill cake if not eating right away, and chill any leftovers.

Tips and notes for this recipe

Sub a thick store bought lemon curd

Obviously, you can use store bought lemon curd. I do it quite often these days, as time is precious when you’re a toddler mom and work full time. Homemade lemon curd will always be my preference, but this buttercream will work just fine with store bought as long as it’s a thicker curd. If you can scoop out a spoonful and hold it upside down without it falling, you have a thick enough curd to use in this buttercream.

Make your own cake flour

Cake flour is something I weirdly always have way too much of when I don’t need it and none of when I actually do need it. We always seem to use it up to get rid of it then regret that later. #firstworldproblems It’s actually easy to make a good substitute for cake flour (it’s not exactly the same but works well). For every cup of flour, you replace 2 tablespoons with cornstarch. Most people say to measure a cup of flour, remove 2 tablespoons, then add 2 of cornstarch.

But I swear by the spoon-then-level method where you spoon your flour into your measuring cup then (holding it over the flour bag/container), use a knife or flat blade to just scrape right over and level it. If you doonk your measuring cup into the flour, you will pack it in and get too much, yielding a dry dessert. So I suggest placing 2 tablespoons (of gently scooped) cornstarch into a 1 cup measuring cup then spooning and leveling your flour on top of that. It’s more accurate that way! For this recipe, it’s easiest to just make a cup of cake flour then save the leftovers for another time. :)

Infuse your milk with lemon peel

My favorite way to infuse milk is overnight in the fridge. Just use a potato peeler to peel the zest (no white pith) of 2-3 lemons. Combine with the milk and put in a sealed jar overnight. Strain before you take it out to warm up (add a little more milk if some was lost in straining—you still need 1 cup total). It’s so easy and gets the best lemon flavor, but it does take some planning ahead.

To infuse your milk the fast way, peel the zest from 2-3 lemons with a potato peeler and combine with the milk in a small saucepan. Heat over medium heat, stirring frequently, until steamy and some bubbles begin to form. Set aside to steep for one hour, then combine with lemon juice as the recipe indicates. I always add an extra splash of milk, as it will reduce in cooking and cooling. As well, you may still need a little more lemon juice to make up for the evaporation. Just be sure you have 1 cup of lemon juice and infused milk once you combine them.

You might also like:

Strawberry Lemonade Cake

Lemon Curd Vanilla Cupcakes

No-Bake Lemon Curd Tart

White Chocolate Raspberry Cupcakes

Mini Key Lime Pies

Lemon & Mascarpone Cake

Print

prep time: 20-25 minutes
bake time: 25-30 minutes
total time: 55 minutes (includes making the buttercream)

servings: 12-16

Ingredients:

for the double lemon cake layers

¼ cup fresh lemon juice
¾ cup whole milk, room temperature (see note for lemon infused milk)
2 cups plus 2 tablespoons cake flour, spooned then leveled (see note above for making your own)
2 teaspoons baking powder
½ teaspoon sea salt
¾ cup unsalted butter, room temperature
1 ⅔ cups granulated sugar
2 tablespoons grated lemon zest (2 large lemons)
3 large eggs, room temperature
2 tablespoons avocado or vegetable oil
1 tablespoon vanilla extract

for the lemon curd mascarpone filling

4 ounces mascarpone cream
¼ cup powdered sugar
¼ cup lemon curd (see note if using store bought)

to assemble

one batch triple lemon buttercream
½ cup lemon curd (optional; see note if using store bought)

Instructions:

First, make your lemon curd (if using homemade). Let it set in the fridge while you make the cake.

make the double lemon cake layers

Preheat oven to 325. Lightly grease and flour two or three 8” or 9” cake pans and line with parchment paper. I like using three pans so I can have more filling. #frosting If making a 6” cake, use three to four pans.
Stir together the milk and lemon juice and set aside while you prep the rest of the ingredients. It will turn into buttermilk while you make everything else. See note for infusing the milk beforehand.
Sift and whisk together cake flour, baking powder, and salt. Set aside.
In a food processor or blender, pulse the sugar and lemon zest, until well blended and no large chunks of zest remain. It should slightly resemble wet sand.
Beat the butter on high until smooth, about 30 seconds. Add the lemon sugar and beat on high until light and fluffy, 2-3 minutes. Scrape the bowl as needed.
Add the eggs, one at a time, beating on high for about 30 seconds until well-blended. Scrape the bowl between eggs. Add the oil and vanilla and beat on high until well-blended, about 30 seconds. Scrape the bowl again.
Add half the flour and mix on low until just barely combined. Add the milk and beat on low until just barely combined. It will look a little separated, but don’t worry. Add the rest of the flour and mix on low until just barely combined, with some streaks of flour still visible. Scrape the sides and bottom of the bowl then beat on medium for 1-2 seconds, just to quickly incorporate the mixture on the bottom (do not overmix).
Divide evenly between prepared pans and spread evenly with a spatula. Bake for 25-30 minutes (less if using three pans), until a toothpick inserted in the middle comes out with a few moist crumbs. Begin checking around 20 minutes so it doesn’t overbake. Rotate pans halfway if not using a convection oven.
Let cake cool in pans 5-10 minutes then remove to a wire rack to cool completely.

make the frosting and lemon curd mascarpone filling

While the cakes cool, make the buttercream.
Once ready to frost, make the mascarpone filling. In a small mixing bowl, gently stir the mascarpone with a rubber spatula until smooth, about 10 seconds. Don’t overmix or whisk it.
Add the powdered sugar and lemon curd and stir until smooth. Taste, adding more powdered sugar if needed for taste or structure, but don’t overdo it.

assemble cake

Fill the cake by adding a thin layer of buttercream on the bottom layer. If making a three layer cake, add half the mascarpone filling (add all of it if making a two layer cake). Spread evenly. Top with a thin layer of lemon curd. Repeat for the middle layer. Add the top layer of cake and frost with a crumb coat, refrigerating beforehand if the cake starts sliding. Refrigerate the crumb coat for 10 minutes then frost to desired thickness.

Enjoy! If not using right away, store in the refrigerator and take out 30 minutes before serving. Refrigerate leftovers, covered in a double layer of plastic wrap with a separate piece directly touching the cut edges of the cake to seal it.