Pie-making has been stressing me out lately. I’ve had some pretty epic pie disasters. Pie crusts oozing massive amounts of butter in the oven, leading to unpleasantly greasy pie crusts that just wouldn’t bake through. There was a pie that I tried to finish on broil to deepen the golden colour of the crust. DO NOT DO THAT! That will lead to scorch marks on the surface of your pie, fire, and tears. I have had issues with pie fillings being over-gelled with tapioca starch, and pie fillings being under-set and too soupy, even raw. I’ve panicked and hyperventilated and failed while trying to make gorgeous top crusts that would be on par with those famous pie-making instagrammers I follow and admire (like lokokitchen and jojoromancer). On the other hand, you wouldn’t necessarily realize the extent of my pie woes because if you scroll through the old posts of this blog, you will see that I have been known to make a few pretty great pies (both visually and in taste), if I may say so myself. There was the maple apple pie where I roasted the apple slices first to soften them so that I could stuff way more fruit into the pie. I used the Nordic Ware pie crust cutter to make the most gorgeous top crust that was a real show-stopper (find it on Amazon). I shared with you a beautiful, traditional maple syrup pie a few years ago. There was a wine-poached pear pie that turned out even better than I’d expected, and let’s not forget the super fun bacon and egg pie, which is the perfect breakfast food. Clearly, according to the records on my blog, I can make pie. Even so, I find that, today, pie-making tends to stress me out, and I know I’m not the only one. So, I decided it was time to go back to basics with a rhubarb pie topped with a basic lattice crust.
The rhubarb pie filling recipe
For this rhubarb pie recipe, I used fresh rhubarb and, just like with many blueberry pie recipes, I cooked half the rhubarb to soften it and allow the juices to run, then mixed that soft rhubarb filling with more fresh rhubarb to make the ultimate rhubarb pie filling. This is a technique I picked up from Stella Parks and it’s how she makes her rhubarb crumbles, actually, but I thought it’d be pie appropriate as well. I sweetened the filling with a mixture of granulated sugar and maple sugar (for some extra flavour) and I added a lot of vanilla, which really enhanced the filling. I also followed Stella Parks trick to add a little baking soda to the filling to reduce that astringent “spinach teeth” filling that rhubarb can leave behind. It certainly did not eliminate the issue, but I felt it was reduced. Definitely something to experiment with next time you make a rhubarb pie or a rhubarb crumble.
A note on thickeners for rhubarb pie
Rhubarb is rather deceptive: if you look at it and you cut into, it doesn’t exactly seem like a juicy fruit, especially when compared to something like a plum or a peach. Rhubarb actually does contain a lot of water (rhubarb is almost 94% water!), which means that as you bake your rhubarb pie, the cells will break down and the water will be forced out into your pie filling, which will result in a very soupy rhubarb pie if you aren’t careful. Like with all pie fillings, you have many options to gel all that liquid: flour, cornstarch, quick-cooking tapioca, tapioca starch. For this pie, I went with tapioca starch and I used a lot of it: 1/2 cup tapioca starch to gel 2 pounds of rhubarb. And though I was VERY worried this was too much tapioca starch because it is a lot more thickener than you would use for, say, an apple pie, I am happy to report that after letting the baked pie rest/gel overnight, the set of the pie was quite perfect. Soft, still a touch fluid, but not soupy at all. This rhubarb pie filling was just right in my opinion, and it continued to thicken so that a full 24 hours after baking the pie, I found that a slice could be cut cleanly from the pie with zero leakage. Call me impressed! So this would mean that you need to use 30 grams (1/4 cup) of tapioca starch to properly set every 450 grams (1 pound) of fresh rhubarb. That’s the rhubarb pie filling ratio to keep in mind for future pies. It works!
In general, tapioca starch has a higher thickening power than flour, which means tapioca starch is what you should use to thicken pies made with very wet fruit, like rhubarb, raspberries, blueberries, etc. On the other hand, for something like an apple pie, you should just go with flour as a thickener.
The pie dough
After unsuccessfully trying other people’s recipes for pie dough that have more butter to achieve a richer crust, more complicated folding techniques for better layering, and different rolling techniques, I decided to throw all those recipes out the window and to return to the pie dough that works for me. This pie dough might be less rich than some, and it’s certainly not as flaky as a rough puff pastry, but you know what? This pie dough works well and is very easy to make and to use. The dough is made in the food processor. It’s extremely easy to roll and to work with, it keeps it’s shape in the oven, it doesn’t ooze butter as it bakes… Screw all the other recipes. This is still my go-to crust. I like it. It works well. It’s forgiving. Most importantly, after hours of pie-making work, this dough doesn’t leave me feeling like the worst baker on the planet like some of the others that have complicated my life over the years.
How to make a lattice crust
Pie has lead to much upset for me over the last year, but I’m happy to report that this rhubarb pie with a lattice crust is one of the best pies I’ve made in a long time and one of the best rhubarb recipes on the blog. I’m hoping this double crust rhubarb pie is the first of many great pies to come. What pie should I made next?
Double crust rhubarb pie recipe
The best rhubarb pie with lattice crust
Here's a recipe for the best rhubarb pie with a lattice pie crust. It's perfect! The rhubarb pie filling is thickened with tapioca starch (or tapioca flour), with just the right amount to allow the juices to thicken and set without being gluey. This pie is made with an all-butter pie crust so it is flaky and tender. It rolls out easily and the pie dough is easy because it's made in the food processor. Perfect pie shouldn't be hard with this recipe!
Rhubarb pie filling thickened with tapioca starch
- 900 grams trimmed rhubarb 2 lb
- 150 grams granulated sugar 3/4 cup
- 150 grams maple sugar 3/4 cup
- 60 g tapioca starch (or tapioca flour) 1/2 cup
- 1/4 tsp fine kosher salt
- 1/8 tsp baking soda
- 1 tbsp vanilla extract
Easy all-butter pie dough made in food processor
- 312 grams all-purpose flour 2 1/2 cups
- 1 tbsp granulated sugar
- 1 tsp fine kosher salt
- 173 grams cold cubes of unsalted butter 3/4 cups
- 100 mL water 7 tbsp
- 1 tbsp milk
- 1 tbsp turbinado
Start by making the rhubarb pie filling
Preheat the oven to 400ºF.
Slice the rhubarb into 1/2-inch to 1-inch chunks. Place half of the chopped rhubarb into a 8x8 non-reactive glass baking (I used a Pyrex baking dish you can find on Amazon). Mix it with the granulated sugar, maple sugar, tapioca flour, and salt. Cover tightly with aluminum foil.
Bake for 30 minutes or until the fruit is soft and the juices have run.
Remove from the oven and add baking soda. Mix well. Add the rest of the rhubarb and the vanilla, stir, and transfer to a bowl then place in freezer to chill.
Meanwhile, make the easy all-butter pie dough in the food processor
In the bowl of a food processor fitted with the metal blade, combine the flour, sugar, and salt. Add the cold butter and pulse to form a coarse crumble.
Add the water and pulse it in, then let the food processor run just until the dough comes together. I bought my Cuisinart Food Processor on Amazon.
Divide the dough in two and transfer both pieces to your work surface. Shape one piece into a disk. Shape the other into a rectangle. Wrap both in plastic wrap and chill for 1 hour.
After 45 minutes of chilling. Retrieve the rectangle of dough. Roll it to a 10x15 rectangle on a floured surface. Transfer to a big cookie sheet and chill again.
Roll the disk to a 14" circle. Transfer to metal pie plate and fit it in place. Pour the chilled filling into the pie and smooth it so it's even. Place in the fridge.
Retrieve the big 10x15 rectangle of dough. Cut it into at least 12 one-inch strips. Take the pie out of the fridge and place 6 strips side by side vertically.
Now weave in the other 6 strips horizontally to form a lattice (check out the video). Trim and crimp the edges.
Chill the pie in the fridge for 45 minutes. Meanwhile place a large cookie sheet on the bottom rack of the oven. You will bake the pie on this sheet so make sure there's enough headspace for a pie!
When the pie has chilled, brush the surface of the lattice with milk and sprinkle with turbinado. Bake the pie on the bottom rack on the preheated cookie sheet for 30 minutes at 400ºF. Lower the oven temperature to 350ºF and continue baking until the edges and top of the pie crust are golden brown. The filling should be bubbling and very hot. This takes at least 50–60 minutes more of baking.
Let the pie cool to room temperature, preferably overnight (even 24 hours) so that the pie sets properly before serving.
Janice Lawandi is chemist-turned-baker, working as a recipe developer in Montreal, Quebec, Canada. She studied pastry at Le Cordon Bleu in Ottawa and cooking at l’Académie Culinaire. She has a BSc in Biochemistry from Concordia University and a PhD in Chemistry from McGill University.