rhubarb shortbread squares

Summer in Vermont is idyllic, there’s no question. But I will admit one thing that is a teeny bit disappointing. The fruit season takes forever to get going here. Strawberries, which I think of as a May fruit from my Illinois days, aren’t ready for picking until mid to late June. And the rest of the berries don’t even come around until July. So for a fruit pie lover in springtime here, it’s pretty much all rhubarb all the time. I was so excited when my daughter turned six months old in mid-June, that her first taste of solid food would be some uber-fresh tender summer produce from the Farmer’s Market. Imagine my dismay when I went there and saw nothing but plant starts, salad greens, and rhubarb. Spoiler alert: we gave her a banana instead, so it worked out OK.

Prepared well, rhubarb is actually pretty delicious, mouthwateringly tangy and so gorgeous with its pinks and reds fading into pale green. I fell in love with this rhubarb curd shortbread recipe I found on food52 a few years ago. I’ve made it tons of times and have developed my own tweaks and tricks so I’m sharing my adaptation of it here. It’s actually getting to be kind of like a game of telephone, this recipe – Rivka, who submitted it to food52, and has a terrific food blog of her own by the way, adapted it from Cook and Eat, who got the rhubarb curd recipe from Ginger Tablet. So I guess I’ve got a lot of chutzpah to think I can improve upon what all those actual food bloggers did. But seriously guys, my way is a leetle bit better. Kidding. Sort of. Not really.

So basically, you chop up a bunch of rhubarb and bung it in a pan with some sugar and a little water. While that’s cooking, go and make your shortbread. Throw a stick and a half of chopped up butter into your Cuisinart.

Have your three year-old sous chef add the flour for you.

Go check on your rhubarb. Whoa, a lot of juice has come out of it! Don’t worry, that’s normal. You want it to cook until it’s totally submerged, and soft enough to fall apart.

Now for the first genius part of this recipe. Spices in the shortbread. I would never have thought to combine spices like cloves, ginger, and cinnamon with rhubarb, but it’s perfect together. So perfect that I went ahead and made it even perfecter by adding two of my favorite dessert seasonings, cardamom and nutmeg.

Blend the whole shebang together until it looks like this:

Then dump it all into a baking pan and press evenly into a nice crust.

Chuck it in the oven on 350 and bake til golden. By now your rhubarb should be soft enough that you can do this to it just by mooshing with your wooden spoon. 

But we don’t want it just moosh soft, we want it puree soft. Like a smooth pudding. Like an expensive face cream. So get in there with your immersion blender.

Looks appetizing, doesn’t it? Once in a while I find rhubarb stalks that are red all the way up and create a beautiful pink puree. But more often than not, it looks like something out of a Gerber jar. Not pretty. So let’s call in a little of nature’s food coloring. Raspberries. I always have a bag in my freezer for smoothies, so I just made a tiny bit of raspberry coulis. Half a cup of frozen raspberries, a tablespoon of sugar, and some vigorous stirring over medium heat makes this:

Strain it into your rhubarb and you will get something that looks like this. Much prettier.

When your shortbread looks like this, it’s ready to come out of the oven and cool on a rack.

While it’s cooling, mix together some egg yolks, sugar, and lemon zest. Add the rhubarb a scoop at a time and then place the bowl over a double boiler and for god’s sake, keep stirring. After about 5 minutes, it should be warmed through and thickened. I didn’t take any pictures of this part because the steam from the double boiler kept fogging my camera lens, but it looks pretty much like eggs mixed with sugar mixed with pink stuff. When it’s done, spread it over the shortbread and bake 10 more minutes at 350.

Droool… seriously you guys, these are so good my mouth is watering just thinking about them. I have one more left in the pan downstairs, I’d better go eat it before the kids wake up…

Rhubarb Shortbread Squares
makes 16 bars

For the rhubarb curd:

• 3/4 pounds rhubarb
• 2 tablespoons water
• 1/4 cup sugar
• 1/2 cup frozen or fresh raspberries *optional
• 1 tablespoon sugar *optional
• 4 egg yolks
• 1/3 cup sugar
• 1 teaspoon lemon zest
• 3 tablespoons softened butter

For the shortbread:

• 12 tablespoons cold butter, cut into chunks
• 1/4 cup powdered sugar
• 1/2 teaspoon salt
• 1 1/2 cups all-purpose flour
• 1/4 teaspoon powdered ginger
• 1/4 teaspoon cinnamon
• 1/4 teaspoon cardamom
• 1/4 teaspoon nutmeg
• 1 pinch cloves

1. Cut rhubarb into 1-inch pieces. Add rhubarb, 1/4 cup sugar, and water to a saucepan and cook over medium heat until rhubarb falls apart. Remove from heat and puree with immersion blender. If it looks pink and beautiful, you’re done for now. If it’s not pretty enough for you, cook the raspberries with 1 tablespoon of sugar in a small pan over medium heat, stirring until all the berries are mashed and the juice has thickened to a syrupy consistency. Press the cooked raspberries through a fine mesh strainer into the pot of pureed rhubarb and stir to blend.

2.Preheat oven to 350. Put all the shortbread ingredients in a food processor and mix until combined. Dump dough into an 8 or 9-inch square baking pan and press evenly to the edges. Bake 30 minutes until light golden brown. Place the pan on a rack to cool, but don’t turn off the oven.

3. Fill the pot of a double boiler with a couple of inches of water. Place the bowl of the double boiler on the counter, and add the egg yolks, butter, 1/3 cup sugar, and lemon zest, mixing well. Add the rhubarb one spoonful at a time and stir until well combined. Place over the simmering pot and continue stirring for about 5 minutes, until the curd is warm and thickened. Remove from heat.

4. Spread the rhubarb curd over the cooled shortbread crust and bake at 350 for 10 more minutes. Cool to room temperature on the counter, then store, covered, in the refrigerator until ready to cut and serve.