Step 1

Prepare, parbake, and press the tart crust as directed. Lower the oven temperature to 325ºF.

Step 2

Place the butter and blood orange zest in a heatproof bowl. Place a mesh strainer over the bowl and set aside.

Step 3

In a medium, heavy-bottomed saucepan, whisk together the sugar, salt, eggs, and egg yolks to combine. Gradually whisk in the blood orange juice and lemon juice until combined.

Step 4

Place the pot over medium-low heat and cook, stirring constantly with a heatproof silicone spatula, until the mixture thickens slightly and reaches 160-165ºF on an instant-read thermometer, 5–10 minutes. As you stir, be sure to scrape the entire bottom and corners of the pan, so that the mixture heats as evenly as possible. It will start out thick and cloudy from the undissolved sugar, then will turn thin and translucent, and finally begin to thicken and turn cloudy again as the eggs cook. Lower the heat to very low as it gets closer to being done. If the mixture starts to curdle or bubble, immediately remove it from the heat and proceed to the next step.

Step 5

Immediately pour the curd through the strainer and into the bowl of butter to stop the cooking. Whisk to incorporate the butter and orange zest, making sure there are no clumps of orange zest.

Step 6

Pour the cooked curd over the baked and pressed down crust. If you have extra curd, you can save it in the refrigerator for up to 1 week. It's delicious swirled into yogurt or slathered on toast or biscuits.

Step 7

Bake the tart at 325ºF (don’t forget to lower the oven temp!) until the sides are barely puffed and the center wobbles like firm Jell-O when you give it a gentle shake, 15–25 minutes. (Some readers have reported that the curd took longer than this to bake, so go by the way it looks and not the time!) It should not be wet or watery looking (underbaked), nor should it be puffed in the center or cracking (overbaked). Remove the tart from the oven and let cool to room temperature for about an hour, then chill until firm, 3-4 hours or overnight.

Step 8

Whip together the crème fraiche and heavy cream until the mixture holds firm peaks. Pipe over the crust if you like, or serve it to the side of the tart.

Step 9

When the tart is cold, loosen and remove the sides of the tart crust and slide it onto a cutting board. Decorate the tart with blood orange wedges, bee pollen, and/or dried edible flower petals if you like.

Step 10

Cut into wedges with a large, sharp chef's knife. For the cleanest cuts, dip the knife in very hot water and wipe the blade clean between cuts.

Step 11

The tart keeps well, refrigerated, for up to 3 days, though the crust is the crispest within the first 1–2 days.