Rhubarb Meringue Tartlets with Pecan Shortbread Crust

Even though spring has decided to be something of a tease this year, we’re charging ahead with the seasonal desserts here in the 4oz Kitchen. The only food that declares, “Spring has arrived, you clowns!” more than rhubarb, to me, is asparagus; however, working that ingredient into a dessert seems almost as foolhardy as trying to make a chocolate cake with beets, and we all remember how that turned out (okay, that beet cake was six kinds of awesome, but I don’t want to press my luck in the roulette of vegetable/dessert combos). So we'll save the asparagus for next time...perhaps in a savory scone or popover of some sort. As for this week, rhubarb will suffice.

A few weeks ago, Emily Hilliard wrote about a rhubarb meringue tart on Nothing in the House, and I’ve been hankering to try it ever since. The long holiday weekend afforded me enough time to make my dreams a reality (and to write in stultifyingly bland clichés…but can’t my vocabulary take a vacation too?).

I’ve been acquainted with rhubarb as long as I can remember. We had a tired, old rhubarb bush, planted by my great-grandparents, living next to our cottage up north, and in the years when it could muster enough chutzpah to produce a few healthy stalks, my dad would always use them to make pie. Now, this year, he’s already made a few of what I’ve come to consider his signature dish, so I think even if Emily hadn’t written about it, I’d ‘ve felt compelled to keep up with family tradition and crank out some sort of rhubarb-related pastry, but I’m really excited about the finished result of this particular recipe. While usually the word ‘curd’ is not one that immediately appeals to the palate, this one is a jaw-dropper...in the good way.

Ingredient line-up for the pecan shortbread crust.

First the dry ingredients and pecans go into the food processor, followed by a generous helping of cold butter.

A few more pulses and our dough is ready to be wrapped and chilled. Recipes often instruct dough to be made into a ball before wrapping, but if I know I'm going to be rolling it out later on (versus just piecing it into the pan), I like to go for a disc shape instead. This, along with letting the chilled dough stand at room temp for about 10 minutes before touching it with a rolling pin, generally makes the whole process go much more smoothly. 

The tart crust baked under foil and pie weights for 20 minutes and then uncovered for another 10. I had enough dough to fill all six of my mini-tart ramekins with a good thick crust and then had enough left over for three 4-oz jars as well. (Somebody may have gotten a little overzealous with her fork-hole-piercing of the crusts -- rest assured there were absolutely NO ripples or bubbles from unreleased air in these shells when they were done baking.)

Once the crusts came out of the oven, I set them aside to cool and worked on the filling. Three cups of diced rhubarb, which came from about 1 1/4 lbs of stalks, yielded 1 1/2 cups of puree. I didn't realize how much water the rhubarb itself contained until it began to cook down. With the help of my new immersion blender, the pureeing part of the curd was quick and easy. Said blender was purchased just recently after months if not years of hesitation. But Meijer was having a sale, so I think the universe was trying to tell me it was time to take the plunge already. Definitely no regrets so far.

Making curd is a stressful process, or at least an absorbing one. You’ll notice there are no pictures taken during this part of the recipe. This is because as soon as the rhubarb puree was finished and back on the stove top, the curd-making process began, and I was busy watching for lumps and whisking in yolks and monitoring the temperature to keep it at-but-not-above-185° F (sidebar: a couple of years ago I bought a candy thermometer. I wouldn’t say I use it often, but it’s definitely proven its worth in clutch situations like this).  However, all of the labor was worth it. Much like Willy Wonka’s paradigmatic snozzberry wallpaper, this rhubarb curd actually tastes like rhubarb. Or, more specifically, since rhubarb by itself is intensely, unpleasantly tart, it tastes like rhubarb pie filling. Eating this dessert is like having the exact flavor of rhubarb pie transported to the middle of a buttery, pecan-and-orange-zest-infused shortbread crust and topped with a fluffy, sugary cloud. The result is sensational. 

Once the tart filling was finished and had time to cool to room temperature, I scooped it into the shells with my trusty giant melon-baller (or ice cream scoop...whatever) and popped it into the fridge to set for two hours. Before scooping, I did have to add some pink food coloring to the curd to bring it back to a shade more reminiscent of rhubarb since the egg yolks added a decidedly yellow tinge when they were whisked in. 

While the tarts were in the fridge, I washed and sliced about a cup of strawberries and got my meringue ingredients ready. I opted to include the strawberry layer between the curd and meringue on some of the tarts because rhubarb + strawberry is never a bad combination. This was not a bad addition, but I was almost loath to add anything to distract from the flavor of the tart filling. The real motive behind this choice is the fact that when you buy strawberries, they demand to be used within a certain, fairly slim window, and mine were edging toward the point of no return, so on they went. I'm a little embarrassed how long I took painstakingly arranging my berry slices in pretty patterns on top of the tarts before I realized they would all be covered in meringue in the end. I like to think they tasted better for the extra TLC, regardless.

Five egg whites make meringue in abundance. I had a good bit left over, and in retrospect I wish I’d committed 100% to the thing and heaped my tarts even higher to use all of the topping. 

It took quite a bit of trial and error with various instruments before I found the best way to apply and then fancify the meringue so it would brown in a decorative way. Pro-tip: start with the butter knife, then use the spoon to finish; ditch the spatula entirely. Also, the historians in the audience should take a moment to notice the spoon used here. I was recently given the privilege of inheriting the silver owned by the same great-grandparents who planted the rhubarb in the first place. The spoon pictured is one of Clyde and Elma Taber’s very own. So that’s pretty boss.

When they came out of the oven for the last time, my meringue had toasted to a golden brown and the kitchen smelled like rhubarb pie, which told me I'd done something right. 

I finished this recipe pretty late at night, so once they were cool, I put all the tarts back in the refrigerator to keep overnight, and then rewarded myself with one for breakfast. I'd finished almost the whole thing before I remembered I had an obligation to pause and document for my readers. There is no better companion to morning coffee than a good pastry. And these aren't just good, they're sweet, tangy, light, fruity, and bursting with bright, springtime flavor.   

Rhubarb Meringue Tart with Pecan Shortbread Crust
Slightly modified from Nothing in the House

For the crust:
1 c. pecans, roasted
1 3/4 c. all-purpose flour
1/3 c. sugar
2 tsp. baking powder
9 Tblsp. butter
1 egg
1 egg yolk
1 tsp. vanilla extract
zest of one small orange

For the filling:
3 c. fresh rhubarb, diced
1/4 c. + about 1/2 c. water  (extra ½ c. may not be necessary)
1 1/4 c. sugar
1/4 c. cornstarch
1/4 tsp. salt
5 egg yolks (save whites for meringue)
3 Tblsp. butter, cut into chunks

For the meringue:
5 egg whites
1 tsp. cream of tartar
1/4 c. sugar

Directions

For the crust:
1. Combine roasted pecans, flour, sugar, and baking powder in a food processor and pulse until pecans are finely ground.

2. Add cold butter chunks to the pecan mixture and process until mix is the size of small peas.

3. Add egg, egg yolk, vanilla extract and orange zest and pulse just until dough begins to form.

4. Remove pastry dough from the food processor, form into a disc and wrap tightly in plastic wrap. Chill for at least one hour and up to 1 day.

5. After at least one hour, preheat oven to 350 degrees F and lightly grease and flour the bottom and sides of a 9-inch tart pan or six 4 oz ramekins. Remove the dough from the fridge. Let it sit for 5-10 minutes, then place a sheet of waxed paper over the disc and roll it out to about 1/8” thickness.  If rolling isn’t your thing, Emily says you can also just press it into the bottom and sides of the tart pan. The bottom crust should be slightly thicker than the sides.

6. Pierce bottom and sides with a fork and then place crust in the freezer for about 10 minutes so butter can re-chill.

7. Remove, line with parchment paper and pie weights, then bake for about 20 minutes or until edges are light, golden brown.

8. Remove pie weights and bake for 5-10 more minutes. Take from oven and let cool.

For the filling:
1. Combine diced rhubarb and 1/4 c. water in a saucepan and bring to a boil over medium heat. Let cook until rhubarb is soft and begins to break down.

2. With an immersion blender (or a stand blender), purée until smooth and set aside to cool slightly.

3. Once cooled, pour into a 2-cup measuring cup and add enough water to bring purée to 1 1/2 c if necessary. Then pour the rhubarb mixture back into the saucepan.

4. Add sugar, salt, and cornstarch to the purée mixture and cook over medium heat until it begins to thicken. Whisk constantly to prevent lumps.

5. Add in egg yolks, whisking after each addition.

6. Continue to cook until mixture coats the back of a spoon, or reads 185° F on a candy thermometer.

7. Remove from heat and stir in the butter. Let cool to room temperature. Once cooled, pour filling into pie crust, cover with plastic wrap and place in the fridge for about 2 hours.

8. If desired, slice strawberries and arrange them in a thin layer over the filling before topping with meringue.

 For the meringue:
1. Once filling has chilled for 2 hours, and you’ve added strawberries if you want, preheat oven to 375° F.

2. In a medium mixing bowl, mix egg whites and cream of tartar on high until egg whites begin to form medium peaks.

3. Continue to beat eggs, gradually adding in sugar. Again continue to beat eggs until they are glossy and can form stiff peaks.

4. Spread over rhubarb filling, making sure the meringue seals the edge of the pie. Use the back of a spoon to curl meringue decoratively.

5. Bake for 12-15 minutes or until egg whites begin to brown. Serve chilled, at room temperature, or alongside a cup of coffee.