Lemon Rhubarb Streusel Scones

Preheat oven to 425 degrees F.

For scones, in large mixing bowl, stir together flours, brown sugar, baking powder, baking soda and salt. Cut in butter (with pastry blender or your hands) until mixture resembles coarse crumbs. Toss rhubarb and lemon zest with flour mixture.

Whisk together egg yolk and sour cream, make a well in the center of dry ingredients and add sour cream and egg all at once. Stir with a fork until combined (dough may seem dry). Turn onto a lightly floured surface and knead gently about 10 times, until fairly smooth. Pat dough into a 9″ circle and transfer to parchment paper-lined baking sheet.

For streusel topping, combine oats, flour, 1/4 cup brown sugar and melted butter. Gently pat streusel into surface of dough and cut the dough circle into 12 wedges. Do not separate the wedges.

Bake for 20-25 minutes, until cooked through and topping is lightly browned and crisp.

For glaze, combine icing sugar, vanilla, and milk. Allow scones to cool slightly before drizzling on glaze.