Strawberry and Rhubarb Crumble

Despite being a lover of crumble (comfort food that reminds me of Sunday afternoons at home with my family? I'm in!), this was the first time I'd ever tried to make it. Turns out it really isn't as tricky as I'd supposed.
I had an idle afternoon, about half a punnet of strawberries in the fridge, a tin of rhubarb in the cupboard (which had traveled to three different houses with me - the marvels of canned food! ...or the wonders of moving three times in eight months. Either way: wowzers), and a copy of Dan Lepard's Short and Sweet on loan from my local library. So why not?
For the fruit filling, I drained the rhubarb, chopped up the strawberries, mixed it all together, and liberally sprinkled with sugar (everything's better with sugar). I might be a bit more inventive next time and add some cinnamon and things (or just remember to have custard. That would help too.)
Whilst trying to find a version of Mr Lepard's crumble mix online, I happened across this wonder of a recipe: Passionfruit Crumble Cake. Definitely one to try, if I can ever find a passionfruit at the supermarket or grocer's (is it only me who has this problem? Are they only in season for a limited time? I know of at least two bars which always have passion-fruit halves to put in their cocktails, so they must be available somewhere!)