Rhubarb Brown Sugar Crumble

A generous amount of oatmeal streusel tops this crumble,
providing a crunchy contrast to the tart, juicy filling.
Vanilla ice cream is a natural with this tasty favorite.

Ingredients:
1 Tbs. unsalted butter, softened at room temperature

For the topping:
4-1/2 oz. (1 cup) all-purpose flour
1 cup lightly packed light brown sugar
1/2 cup old-fashioned oats
1/2 tsp. ground cinnamon
1/4 tsp. kosher salt
4 oz. (8 Tbs.) cold unsalted butter, cut into small pieces

For the filling:
7 cups 1/3-inch-thick sliced rhubarb (about 2 lb.)
1 cup lightly packed light brown sugar
1/4 cup cornstarch
1 Tbs. fresh lemon juice
2 tsp. finely grated lemon zest
(from 1 medium lemon, using a rasp-style grater)
1/4 tsp. kosher salt

Directions:
Position a rack in the center of the oven
and heat the oven to 350 degres F.
Grease an 8x8-inch baking dish
with the softened butter.

Make the topping:
In a food processor, combine the flour,
brown sugar, oats, cinnamon, and salt
and pulse several times to combine.
Add the cold butter and pulse until
the mixture has the texture of coarse meal
and clumps together when squeezed lightly,
about 1 minute.

Make the filling:
Combine the rhubarb, brown sugar, cornstarch,
lemon juice, lemon zest, and salt in a large bowl
and stir with a spatula until evenly mixed.
Transfer the rhubarb mixture to the baking pan,
and sprinkle the topping evenly over the fruit;
the pan will be very full,
but the crumble will settle as it bakes.

Bake until the topping is lightly browned,
the rhubarb is tender and the juices are
bubbling thickly around the edges,
45 to 60 minutes.
Transfer to a rack to cool to warm
or room temperature and to allow the juices to thicken,
at least 1 hour.