She ain’t much to look at—come on, aren’t we all a little shaggy these days?—but she makes up for any deficits in plate appeal with undeniable belly appeal.
This is a moist cake—lightly sweet with tiny, jammy pockets of Tart thanks to baked-in hunks of diced fresh rhubarb—that you’ll enjoy as a breakfast or brunch bake, an afternoon-break cake, or as straight-up dessert (try it warmed and topped with a little vanilla ice cream).
Rhubarb Crumb Cake
Adapted lightly from Melissa Clark’s quarantine-friendly Pantry Crumb Cake—which she designed to accommodate various spices (say, cinnamon, ginger, cardamom, nutmeg), various liquids (acidified milk, sour cream, buttermilk, yogurt), and various fresh or frozen fruits (berries, cherries, pears, apples, or even pineapple). Consider making double the topping, which freezes well and can serve as a streusel for a batch of muffins, a wee pie, or a fruit crisp.
For the Crumb Topping
- 1/2 cup packed brown sugar (I use mostly light, with a couple spoonfuls of dark)
- 1/4 cup unsalted butter, melted (that’s 4 tbsp, or half a stick)
- 1/3 cup all-purpose flour
- 1/3 cup old-fashioned, rolled oats (not “quick,” not “instant”)
- 1 tsp ground cinnamon
- 1/4 tsp kosher salt
For the Cake
- 1-1/2 cups all-purpose flour
- 1 tsp baking powder
- 1/4 tsp baking soda
- 1/4 tsp kosher salt
- 1/2 cup unsalted butter, room temperature (8 tbsp or one stick)
- 1/2 cup granulated sugar
- 2 large eggs, room temperature
- 2 tsp vanilla extract
- grated zest of half an orange (or lemon)
- 2/3 cup buttermilk (you can easily sub yogurt or sour cream)
- 3/4 cup rhubarb pieces (between a 1/4- and 1/2-inch dice is good)
Heat oven to 350º, and butter an 8-inch square pan.
Prepare the topping first, so it can chill a bit in the fridge. Simply mix all the crumble ingredients in a medium bowl, smushing and scraping with a rubber spatula or wooden spoon until you get a nice mix of different-sized clumps. Stick the bowl in the refrigerator while you make the cake batter.
Whisk the the dry ingredients together in a small bowl.
Separately, cream together the butter and sugar for a good two minutes, until smooth and lightened in color (I use a stand mixer but if you’re missing your gym, stirring this by hand makes a great upper-body cross-fit station). Scrape down the bowl, then beat in the eggs, one at a time. Scrape again, then mix in the vanilla.
Sandwich the dry and wet ingredients next by adding half the flour mixture and blending briefly; then adding the buttermilk and beating well; then adding the last of the flour, mixing until just incorporated. Scrape down the sides of the bowl once last time, then fold in the orange zest.
Scoop out about half the batter into the prepared pan; use the spatula to work an even layer all the way into the corners.
Scatter the rhubarb pieces across the top, then smooth the rest of the batter over that. Pull the bowl of crumble from the fridge, break apart the pieces with your fingers, and spread the topping evenly atop the cake batter.
Bake for about 45 minutes (last week, it was done in 40, this one took the full 45), until the top is nicely browned and a tester toothpick inserted into the center of the cake comes out clean.
Place the pan on a rack and let the cake cool for 15 minutes or so before you slice in (though, naturally, plucking off buttery, brown-sugary nuggets is acceptable sampling).
Leftovers keep nicely for a couple days. Just cover the pan loosely with foil. And don’t forget to re-cover it after you pinch off a hunk whenever you walk by the counter.