Stan's rhubarb crumble shortcake bars are a yummy twist on that British summer favourite, rhubarb crumble, and are named for my maternal grandfather, who adored rhubarb. The crispy crumble topping covers a layer of sweet blueberries and slightly tart rhubarb, spread upon a base of delicious, buttery shortbread.
Preheat the oven to 190°C (375°F/gas mark 5), and line a roasting pan/baking tin or oven dish, which is at least 5cm (2") deep, with baking parchment.
Wash the rhubarb, and cut up into big chunks. Place into a large saucepan, cover with the sugar, add around 3 tablespoon water, put the lid on, bring to the boil, and rapidly steam for 5 mins.
Using a sieve or conical/chinoise strainer, drain the rhubarb over a large bowl, gently pressing down with the back of a spoon to ensure as much liquid as possible is removed. Leave the fruit in the sieve, over the bowl, to cool. (note 2)
To make the shortbread, cream together together the butter and sugar, then add the flour, and mix together to form a smooth dough. I find it easiest to use my hands for the last part.
Rest the dough in the 'fridge for 30 mins, then turn out onto a lightly-floured board, and carefully roll out until it's about 1.5 cm (c.½") thick, and the same shape as your baking tin. (note 3)
Place the dough into the baking tin, and bake for around 20-25 minutes or so, until the shortbread is a pale golden brown.
Remove from the oven, turn the heat up to 200°C (400°F/gas mark 6), and set the shortbread aside to cool.
Make the crumble topping by rubbing together the butter and flour until it resembles breadcrumbs, and then stir in the sugar.
Put it all together by spooning the rhubarb evenly over the shortbread base, sprinkle over the blueberries, and then cover everything with the crumble topping. Return to the oven, and bake for around 15 minutes, until the crumble starts to turn golden.
Once cooked, remove from the oven, and leave in the tin to cool down. When it's cool, remove from the tin, and cut into 12 bars.
Store in an airtight container... if it lasts that long!
I rarely buy vegan spread or butter now, instead I make my own. One of my most used recipes is from my friend, Mel, over at A Virtual Vegan. Check out her easy vegan butter.
Do make sure you drain the rhubarb properly once it's cooked, or else you will end up with a bit of a soggy bottom. It will still be delicious of course, but these bars should be soft, not sludgy!
If you find that the shortbread dough is fragile, and breaks when you move it, roll it out on some parchment, and then carefully slide the whole thing onto the baking tin.
This recipe has been updated, and new images added.