How do you make a strawberry-rhubarb crumble? Kick it in the crotch

Ah, mid-June. When the green of spring (or in this case the thaw) is slowly transitioning into the lazy days of summer. The sun sets later, making way for a relaxing drink on the porch after a long day of work and a delicious dinner. But what to make for dessert? The garden is not ready to share its bounty yet—except for strawberries and rhubarb. The rhubarb plant is hardy and, when dormant, can withstand the harshest Minnesota winters. It makes an appearance when the trees start to bud, leading to flourish in direct sunlight on the hottest days of summer.

The two fruits are a match made in heaven, making them the starring roles in strawberry-rhubarb crumble. What makes for the perfect strawberry rhubarb crumble? Is it the butter? The fresh strawberries? The tart rhubarb? All of these are key ingredients, but the secret is cornstarch. The tiny ingredient adds an extra crunch to the dense, delicious crust.

Ingredients

Filling

1 lb. rhubarb, cut into 1/2 inch pieces

1 quart strawberries, hulled and quartered

1/4 cup sugar

1 tsp. pure vanilla extract

Pinch of salt

Crumb crust

3/4 cup all purpose flour

3/4 cup quick cooking oats

1 tsp. cornstarch

1/4 tsp. salt

1 stick (8 tbsp.) butter

1/4 cup granulated sugar

1/4 cup light brown sugar

1/4 tsp. pure vanilla extract

1 egg yolk at room temperature

1. Preheat the oven to 350°. In a large bowl, mix the strawberries and rhubarb with the sugar, vanilla, and salt. Leave at room temperature for 30 minutes, stirring occasionally.
2. In another bowl, mix the flour, oats, baking soda, cornstarch, and salt. In another bowl (using a freestanding mixer or a handmixer) cream the butter with both sugars until fluffy, about 3 minutes. Scrape down the side of the bowl. Add the egg yolk and vanilla and beat at medium-high speed for 2 minutes. Scrape down the bowl again. Add the flour mixture and mix at low speed just until incorporated.
3. Pour the fruit into the baking dish. Dollop teaspoon-size clumps of the batter over the fruit. Bake until the topping is deeply browned and the juices bubbling up around it appear thickened, about 45 minutes. Let cool slightly; serve warm with vanilla ice cream if desired.