RHUBARB CRUMB CAKE

Steps:

• Preheat oven to 350 degrees. Toss rhubarb with 1/4 cup sugar. Let stand, tossing occasionally, until sugar dissolves, about 30 minutes. To make streusel, stir together 1/2 cup flour, brown sugar, and 1/4 teaspoon salt. Using your fingers, cut in cold butter until medium clumps form. Press mixture into bottom of bowl; refrigerate until ready to use, at least 20 minutes.
• Butter a 9-inch round cake pan and line bottom with parchment; butter parchment. Dust pan with flour; tap out excess. Whisk together baking powder and remaining 1 1/4 cups flour and 1/2 teaspoon salt. In another bowl, stir together room-temperature butter and remaining 3/4 cup sugar. Whisk in eggs, one at a time. Fold in half of flour mixture, then sour cream and zest. Stir in remaining flour mixture just to combine. Spread batter in bottom of prepared pan.
• Break streusel into large pieces; sprinkle half over batter. Strain rhubarb (reserving syrup); scatter over batter, then top with rest of streusel. Bake until cake pulls away from sides of pan and a tester inserted in center comes out clean, 40 to 45 minutes. Let cool 20 minutes. Invert onto a wire rack; let cool completely. Whip cream to soft peaks; sweeten to taste with syrup. Whisk until soft peaks return and serve with cake.