Hibiscus Grapefruit Tartlets with Ginger Meringue

In case you missed it, yesterday was Pi Day. Every year I try to bake at least one sweet or savory pie-like creation for the occasion, and this time I wanted to do something different and exciting so I developed this recipe for Hibiscus Grapefruit Tartlets with Ginger Meringue. It’s no secret that I have a thing for winter citrus – since we’re at the tail end of the season I had to squeeze in at least one more recipe with it! I lucked into some incredibly fragrant red grapefruits and decided to make a curd with them, but I wanted to add a special twist so I dug into my stash of dried hibiscus. I’ve featured hibiscus here on the blog in other recipes (see here and here), and honestly if you haven’t tried baking with it yet you’re really missing out. The flavor is tart and tangy with notes of lemon and berries, and it’s a fabulous pairing with the grapefruit here. Plus, it lends the curd an insanely beautiful vivid magenta-like hue (if you’ve ever made grapefruit curd before you know that the eggs pretty much take over and turn it a relatively unremarkable pale yellow). This hibiscus grapefruit curd is totally addictive and spoonable on its own – I’ve kept the sugar level in check so the tart flavors really shine – and when spooned into the crunchy grain-free almond cookie crust and garnished with an airy ginger meringue, it’s positively irresistible. But don’t take my word for it, make this recipe and find out for yourself! Let’s get to it.

The almond cookie crust is up first, so add the dry ingredients to the bowl of a food processor and pulse until you have a uniform dry base. Don’t let the processor just run at full speed or you’ll turn the almond flour into clumps of almond butter.

Here’s how it should look after pulsing – when those clumps of almond flour start to gather, stop processing.

Add the maple syrup, butter or shortening, egg, and vanilla, and process until the dough pulls together into a very soft, sticky dough.

Here’s how the dough will look after it’s processed. It’s VERY soft and sticky, so it needs to be chilled before you bake it. Scrape it onto a sheet of plastic, wrap it tightly, and pop it into the freezer for about 15 minutes. You can preheat the oven now.

While the dough is chilling, prep the ingredients for the curd – zest and juice the grapefruit,  measure everything out, separate and beat the eggs and egg yolks, and grind that dried hibiscus a bit. The key here is to break down the hibiscus into smaller pieces without totally pulverizing it. You will get some powder, but you want a good portion of it to remain in coarse chunks so you can strain most of it out of the cooked curd. Don’t be tempted to skip the grinding step though – if you don’t crush it somewhat the hibiscus won’t steep properly as the curd cooks, and you’ll miss out on a lot of that tart flavor and stunning color. I blitz the hibiscus in a small blender or spice grinder to break it down, but in a pinch you can seal it in a zipper bag and smack it a bunch of times with a rolling pin or the flat bottom of a skillet.

Once the dough is firm enough to handle, pull it from the freezer and divide into four equal portions. Drop a mound into the center of each tartlet pan – I highly recommend using pans with removable bottoms for this recipe.

The dough will still be soft and somewhat sticky, so grab the sheet of plastic that you used to wrap it for the freezer, and lay it over the surface. Now you can work the dough outward from the center and press it up the sides of the pans without sticking issues. I like to use a tart tamper to do this, but your hands will do the job just fine. Once the crusts are formed, dock the bottoms with a fork, place the pans on a small tray, and chill them in the freezer for 15 minutes. After they’ve firmed up a bit, line each one with a small sheet of foil or parchment, fill with your weights of choice (I like ceramic pie weights), and bake for 15 minutes, just until the edges are set and beginning to show a hint of golden color. Remove the liners and weights and pop the tray back into the oven for another 5 minutes, then transfer the pans a rack to cool.

While the crusts are cooling, make the hibiscus grapefruit curd. Get the sugar, arrowroot, salt, ginger, and grapefruit juice whisked up in your saucepan, whisk in the eggs, and stir in the grapefruit zest and dried hibiscus. Cook the mixture over medium low heat, stirring and scraping frequently with a spatula or wooden spoon. Curd typically cooks in a few minutes so you need to stay at the stove and keep an eye on it. The target temperature is 155°F, so if you have an instant-read digital thermometer you can use that to check. If not, watch for the mixture to get noticeably thick, then coat the back of your spatula or spoon with it and run a finger through the coating – if the trail you left behind stays clear and the curd doesn’t run back in, it’s ready.

Can you believe the mixture from the previous photo turned into this in just 5 minutes?! We’re not done yet. Once the curd is cooked you need to strain out the solids, so set the pan over a heatproof bowl and work the curd through with a spoon or spatula, scraping and pressing to make sure you get all the curd into the bowl beneath.

See? All those coarse pieces of hibiscus  – and a few grapefruit seeds – stayed behind. No one wants crunchy curd.

Gorgeous, right? It’s pretty thick and gloppy though – a proper curd needs to be finished with butter, so add yours now and stir it in to melt and incorporate into the curd.

See the difference the butter makes? Silky, smooth, and absolutely stunning.

The curd should have cooled down from the stirring, but test it with a finger to be sure. Once it’s barely warm, you can spoon it into the par-baked crusts. If you’re making the components ahead of time to serve later, refrigerate the curd, and wrap the crusts in plastic and keep at room temperature.

When I make this as mini tartlets I use a cookie dough scoop to portion out the filling. It’s more accurate and keeps the mess in check. Put the filled crusts back on a tray, slide it into the oven and bake for 8-10 minutes until the tops are set.

Let the baked tartlets cool on a rack while you make the ginger meringue for garnish.

There’s no need to break out your giant stand mixer for this meringue since you’re only whipping two egg whites. I use a medium-size mixing bowl and my electric handheld mixer with the whisk attachment (not the beaters).

The meringue needs to be stiff enough to pipe and hold its shape, so be patient. See how that peak is tilting off to the side a bit? This needs to be whipped a bit longer. When you can hold the whisk upright and the peak stays absolutely in place, it’s firm enough to pipe. At that point you can transfer it to your piping bag. I like to use a star tip, but a round one is fine too. Pipe the meringue onto the cooled tartlets however you’d like – you can cover part or all of the surface, it’s really a matter of preference. Once the meringue is piped on, grab a kitchen torch and brown the meringue.

That’s it! Grab a fork and enjoy.