This layered, summery blueberry-lemon tart is as stunning as it is delicious. Naturally sweetened, this tart recipe features a vibrant lemon curd layer followed by a perfectly-sweetened blueberry filling.
Table of contents
Where the Recipe is From
I’ve had my nose stuck in the new America’s Test Kitchen cookbook, Naturally Sweet: Bake All Your Favorites with 30% to 50% Less Sugar (America’s Test Kitchen) since mid-July when I received it from America’s Test Kitchen.
This Blueberry–Lemon Curd Tart caught my eye from the very beginning; I kept getting drawn back to its stunning colors and striking layers. And although it takes a few hours to make, it’s fairly easy to prepare and is so refreshingly delicious, delightfully tart, and perfectly sweetened. Honey is used in both the lemon and blueberry layers, pairing well with both fruits. Sucanat is used in the tart crust and offers a deep sweetness with just a touch of molasses.
Having interned at ATK during the summer of 2014, I knew this book, like all of their others, was going to be amazing. Packed full of both classics and new favorites, this book of foolproof recipes was bound to deliver. And did it ever!
Not only is each recipe developed using only natural sweeteners; they are also developed to be lower in sugar content (30-50% lower than their traditional counterparts). And honestly, I was a bit skeptical about the book before I received it.
I assumed that if the recipes were lower in sugar they must be calling for sweeteners like Splenda, Stevia, or Monkfruit; sweeteners I would rather not use due to their flavor and extensive processing. I was pleasantly surprised to find that wasn’t the case, which makes these recipes that much more impressive. The editors at ATK had to completely re-think the baking and cooking process of recipes utilizing sugar.
Baking with Natural Sweeteners
To really understand the extent of this recipe development it’s important to know how sugar affects different recipes, specifically in baked goods. Sugar is not only used for sweetness, it is largely used for structure, texture, and color, just to name a few.
When creating a low-sugar baked good, one cannot simply decrease the amount of sugar used because the structure and crumb will greatly suffer if other ingredients or processes are not modified. Likewise, natural sweeteners like honey, maple syrup, or Sucanat cannot simply be swapped out for granulated sugar in baking due to various melting points, moisture contents, and absorption capabilities. Thus, ingredient ratios and processes were completely reanalyzed for this book.
As you work your way through Naturally Sweet, the editors at ATK walk you through their thought and development processes, and explain why the recipes were developed in the way they were. They take note of what tasters liked and disliked, give justifications for which sweetener they used, and explain what conventional cooking and baking processes they had to rethink.
This book challenges those hard-fast laws of baking and cooking, giving us cooks the courage and power to question our habits in the kitchen. After all, isn’t that the beauty of cooking? Isn’t that the art of it? Unlike many aspects of our lives, the rules in cooking are meant to be challenged, pushed, and broken.
How to Make a Tart Crust
- Pulse dry ingredients together, scatter butter over top and pulse until a coarse meal is formed. Add yolk and cream mixture and pulse until a dough comes together.
- Turn dough out onto a work surface
- Form dough into a disk and wrap tightly with plastic wrap; chill 1 hour.
- Roll dough out then press into bottom of pan and up sides; freeze until form, about 30 minutes.
- Blind bake crust until starting to brown and dry to the touch. To blind bake, line the unbaked tart crust with foil, fill with baking weights (or beans) and bake.
How to Make Homemade Lemon Curd
- use fresh lemon juice and zest
It’s absolutely necessary to use fresh lemon juice. The fresh tart flavor is incomparable to the bottled stuff. It’s also important to use fresh lemon zest—yes, ¼ cup is the correct amount. You’ll strain it out before serving, so don’t worry, you won’t be picking zest out of your teeth.
- cook the lemon curd
Whisk yolks, egg, honey, lemon zest, lemon juice, and salt together in a saucepan until smooth. Cook lemon curd mixture over medium-low heat, whisking constantly, until mixture has reached 165-degrees and mixture has thickened, this should take 5 to 8 minutes.
Using an instant-read thermometer takes all the guesswork out of making lemon curd (and candy, meat, fish, etc.) This is my all-time favorite instant-read thermometer.
- remove from heat and stir in the butter
Remove saucepan from heat and stir in butter until melted. The butter is important for adding flavor and creating a silky smooth texture. Be sure to use unsalted butter!
- strain the curd
This step is important for two reasons. First, it strains out all of the zest we added at the beginning. And secondly, it acts as a failsafe by straining out any specks of cooked egg (occurs when the mixture is heated too quickly without being agitated or stirred).
- stir in the cream
Adding just a splash of cream creates a silky smooth, luscious curd. The addition of cream to homemade lemon curd is not traditional and can easily be left out but it is delicious.
Tips for Making the Perfect Lemon Blueberry Tart
- Be sure to use a 9-inch round tart pan. If you use a smaller pan you’ll end up having too much filling, and if you use a larger pan you won’t have enough filling.
- Use eggs labeled as “large.” This is essential as it will determine how much lemon curd you end up with.
- Make sure you strain the lemon curd before pouring it into the tart. This will strain out the bits of lemon zest. The zest has already imparted all of its flavor into the curd and by straining it you’ll get a super smooth curd.
Blueberry–Lemon Curd Tart
Classic Tart Crust
- 1 large egg yolk
- 1 tablespoon heavy cream
- ½ teaspoon pure vanilla extract
- ¼ cup (1 ⅓ ounces) Sucanat or ⅓ cup confectioners' sugar*
- 1 ¼ cups (6 ¼ ounces) all-purpose flour
- ¼ teaspoon salt
- 8 tablespoons unsalted butter, cut into ¼-inch pieces and chilled
- ¼ cup lemon zest + ½ cup juice (4 lemons)
- 1 large egg + 5 large yolks
- ⅓ cup + ¼ cup honey
- 4 tablespoons unsalted butter, cut into 4 pieces and chilled
- 2 tablespoons heavy cream
- 10 ounces (2 cups) blueberries
- 2 tablespoons cornstarch
- 2 tablespoons water
- Whisk egg yolk, cream, and vanilla together in bowl. Grind Sucanat in spice grinder until fine and powdery, about 1 minute. Process flour, ground Sucanat, and salt in food processor until combined, about 5 seconds. Scatter chilled butter over top and pulse until mixture resembles coarse cornmeal, about 15 pulses. With process running, add egg yolk mixture and process until dough just comes together, about 12 seconds.
- Form dough into 6-inch disk, wrap tightly in plastic wrap, and refrigerate for 1 hour.
- Let chilled dough sit on counter to soften slightly, about 10 minutes. Roll dough into 11-inch circle on lightly floured counter. Loosely roll dough around rolling pin and gently unroll it onto 9-inch tart pan with removable bottom, letting excess dough hang over edge. Ease dough into pan by gently lifting edge of dough with your hand while pressing into corners and fluted sides of pan with your other hand. Run rolling pin over top of pan to remove any excess dough.
- Wrap dough-lined pan loosely in plastic, place on large plate, and freeze until dough is chilled and firm, about 30 minutes.
- Adjust oven rack to middle position and heat oven to 375ºF. Set dough-lined tart pan on baking sheet, line with double layer of aluminum foil, covering edges to prevent burning, and fill with pie weights.
- Bake until crust is golden brown and set, about 30 minutes, rotating pan halfway through baking. Remove weights and foil and let crust cool.
- Adjust oven rack to middle position and heat oven to 350ºF. Measure out 1 tablespoon lemon juice and set aside.
- Whisk remaining lemon juice, lemon zest, egg and yolks, ⅓ cup honey, and pinch salt in medium saucepan until smooth. Cook over medium-low heat, stirring constantly with rubber spatula, until mixture thickens slightly and registers 165ºF, about 5 minutes.
- Off heat, whisk in chilled butter until melted. Strain lemon curd through fine-mesh strainer into bowl, then gently stir in cream with rubber spatula.
- Pour warm lemon curd into cooled tart crust. Set tart on baking sheet and bake until filling is shiny and opaque and center jiggles slightly when shaken, 10 to 12 minutes, rotating pan halfway through baking. Transfer tart with baking sheet to wire rack and let cool slightly.
- Meanwhile, process blueberries in a food processor until smooth, about 2 minutes. Strain purée through clean fine-mesh strainer into medium saucepan, pressing on solids to extract as much liquid as possible (you should have about ¾ cup); discard solids.
- Whisk in remaining ¼ cup honey and ⅛ teaspoon salt. Whisk cornstarch and water together in a small bowl, then whisk into strained blueberry mixture. Bring to simmer over medium-low heat, stirring constantly, and cook until thickened slightly and registers 170ºF, about 4 minutes. Off heat, whisk in reserved 1 tablespoon lemon juice.
- Pour blueberry mixture evenly over cooled lemon filling. Tap pan lightly on counter to release any air bubbles, then refrigerate until blueberry mixture is set and shiny, about 2 hours.
- To serve, remove outer ring of tart pan, slide thin metal spatula between tart and tart pan bottom, and carefully slide tart onto serving patter or cutting board.
- Original: 42 grams sugar New Recipe: 27 grams sugar
- *don’t have or can’t find sucanat? You can use ⅓ cup confectioners’ sugar (aka powdered sugar) instead. Skip the grinding step of the sugar and add the confectioners’ sugar right to the food processor with the flour and salt. You can also use ¼ cup coconut sugar—you’ll need to grind it as instructed in the recipe. If you use coconut sugar the crust will come out darker and slightly less sweet.
- Dough Make Ahead Tip: Dough can be wrapped tightly in plastic and refrigerate for up to 2 days or frozen for up to 1 month. If frozen, let dough thaw completely on counter before rolling.
- Dough Make Ahead Tip: Dough-lined tart pan can be wrapped tightly in plastic and refrigerated for up to 2 days or frozen for up to 1 month.
- If you’re using this tart crust recipe for a different tart that calls for a fully-cooked tart crust continue baking, uncovered, for an additional 5-10 minutes until deeply golden brown.
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I received a copy of Naturally Sweet: Bake All Your Favorites with 30% to 50% Less Sugar (America’s Test Kitchen) from America’s Test Kitchen, this recipe is used with their permission. This post contains affiliate links.