Rhubarb Raspberry Rye Crumble

Behind the house where my mother-in-law grew up is a rhubarb plant that, as I was told by her father, "has been in our family forever." He told me the variety was called Strawberry Rhubarb, and is one that is especially good for baking.

There are four rhubarb plants in the far corner of my own yard, grown from that original. Viewed from the window above the kitchen sink, they form a green, rustling mound, with their built-in parasol of leaves sheltering carmine stems. They thrive beside raspberry bushes also started in my husband’s grandparents’ garden.

A level of sentimentality for the combination is thus inevitable, yet the pairing of rhubarb and raspberry is undeniably good on the table. I prefer raspberries to strawberries with rhubarb; they seem to stand up to the strident assertiveness of the stalks better, plus I think raspberries take better to baking.

Here the garden’s yield is baked to a heady burgundy compote beneath the earthy cover of rye streusel. That topping is almost a shortbread dough, which makes for a buttery complement to the knife-sharp jammy filling.

Preheat an oven to 375°F (190°C) with a rack in the lower third of the oven. Line a rimmed baking sheet with parchment paper. Grease a 2-quart (2 L) baking dish with butter.

To make the topping, in the bowl of a stand mixer fitted with the paddle attachment, cream together the butter, sugar, and salt on medium-high speed until fluffy, around 3 minutes. Scrape down the sides of the bowl and turn the speed to low. Sprinkle in the oats, flours, almonds, and cardamom; let the machine run until the dry ingredients are incorporated and the mixture starts to gather into a rough streusel, 3 to 5 minutes, scraping down the bowl as needed. Keep in a cool spot or covered in the fridge while you organize the filling.

To make the filling, in a large bowl, combine the rhubarb, raspberries, lemon juice, sugar, tapioca flour, and salt. Split the vanilla bean down its length, scrape the seeds into the bowl, and then add the pod as well. Fold everything until the tapioca disappears. Tip the fruit into the prepared baking dish, including any collected juices. With clean hands, crumble the streusel over the filling, in haphazard and uneven heaps.

Place the dish on the prepared baking sheet and bake until the juices are gurgling with large bubbles and the topping is golden brown, 50 minutes or thereabouts.

Cool on a rack for 30 minutes before considering eating. Serve warm or cold, with vanilla frozen yogurt or whipped cream.

NOTE: The sugar for the filling may be scant for some tastes; both rhubarb and raspberries are sour, and the amount used here keeps the twang that hits the point at the back of your jaw right below the ear—it’s not so much that the muscle clenches, but there’s still a twitch. When I eat the filling with the crumble topping, I feel it all evens out, but still, it is a characteristic to know before going in.

Reprinted from Seven Spoons by Tara O’Brady. Published by Knopf, an imprint of Penguin Random House LLC.