Recipe Rhubarb Shortbread

On top is a silky, tangy layer of rhubarb curd (made like lemon curd) and underneath is a thick, crumbly spiced shortbread. Brilliant! We made this shortbread in a food processor and suggest you do the same, if you have one on hand. The curd takes a bit of elbow grease, it must be said. Think of it as your workout for the day. Once the two basic ingredients are together, simply merge them together with an icing spatula and finish with a few minutes in the oven.

Prep Time: 1 hour 30 minutes
Cook Time: 1 hour 5 minutes
Serves: 16 bars

INGRÉDIENTSFor the Curd

1. 3/4 pound rhubarb (about 6 stalks)
2. 4 tablespoons water
3. 1/4 cup sugar​
4. 4 egg yolks
5. 1/3 cup plus 1/8 cup sugar
6. 1 teaspoon lemon zest
7. 2 teaspoons lemon juice
8. 3 tablespoons butter, cut into pieces

For the Shortbread

1. 12 tablespoons butter, cut into pieces
2. 1/4 cup powdered sugar
3. 1/2 teaspoon salt
4. 1 1/2 cups all-purpose flour
5. 1/4 teaspoon powdered galangal or ginger
6. 1/4 teaspoon cinnamon
7. 1 pinch cloves

PRÉPARATION

1. Wash the rhubarb and chop as little as possible. Cut it into 2.5 cm pieces. In a small saucepan, heat the rhubarb, 1/4 cup sugar, and the water over medium heat. Cook until it breaks down and no whole pieces remain, adding water by the tablespoon if the rhubarb sticks to the bottom of the pan. At this point, use an immersion blender to purée the mixture or (if you're like me and your blender is busy) pass the mixture through a fine sieve. The first method is much simpler.
2. Preheat the oven to 175°C. Now, make the shortbread: blend all the ingredients in a food processor or stand mixer until well combined. Wrap in plastic wrap and refrigerate for about 1 hour. Next, roll out the dough into a 20cm x 20cm square and place it in an 20cm square pan, or pour it into the pan and press it down evenly with your fingertips. Bake for 30 minutes, until golden brown. Let cool on a wire rack or countertop.
3. Add a few inches of water to a double boiler and heat over medium heat. Add the egg yolks, butter, remaining sugar, lemon zest and juice to the boiling water in the double boiler and whisk to combine. Once the sugar has completely dissolved, add the rhubarb purée by the spoonful to temper the eggs. Once all the rhubarb has been added, place the bowl over the pan; the water should be simmering. Continue stirring the rhubarb mixture; after about 5 minutes, the mixture will be hot and slightly thickened. Remove from the heat. Press through a sieve to obtain a smooth, creamy texture.
4. Using an offset spatula, spread the curd evenly over the shortbread. If you didn't eat half the bowl right away, you should have enough curd to form a layer about the thickness of the shortbread; this wasn't the case for me. Bake for another 10 minutes, then remove from the oven and let cool on a wire rack. Refrigerate for about 20 minutes, and you'll find they're firm enough to cut cleanly. Cut into 16 equal bars. Dust with powdered sugar before serving; be careful not to eat them all at once.