for the crust and crumble topping: 1-1/4 c. all-purpose flour 1/2 c. old-fashioned oats 1/2 c. brown sugar 1/2 tsp. kosher salt 1/2 c. unsalted butter, softened (not melted!)
for the rhubarb and cream cheese filling: 8 oz. cream cheese, softened 3/4 c. sugar 1 large egg 1 tsp. pure vanilla extract 1/2 tsp. cinnamon 1/8 tsp. nutmeg 1-1/2 c. chopped rhubarb
Preheat oven to 350°.
for the crust and crumble topping:
In a medium bowl, combine flour, oats, sugar, and salt. With a rigid pastry blender, cut in the butter until well incorporated and pea-sized crumbles are formed. Firmly press half the mixture into an ungreased 9'' x 9'' pan. Set aside remaining mixture.
for the rhubarb and cream cheese filling:
In the bowl of a stand mixer, combine cream cheese, sugar, and egg until very smooth, about 1 minute. Add vanilla, cinnamon, and nutmeg, and blend just to combine. Fold in rhubarb. Spread filling over crust. Sprinkle remaining crust crumbles over the top of the filling. Bake for 40 minutes.
Store in refrigerator. Serve with a scoop of vanilla ice cream, or freshly whipped and sweetened cream with a light touch of vanilla, cinnamon, and nutmeg.