For the Rhubarb Scones simply make my classic scones dough using these instructions (or by watching the video above), and use the above listed sour cream, milk and vanilla as liquid ingredients. ( in the original post, I list 1/2 cup buttermilk and 1/2 cup sour cream so we want to replace those by using the sour cream and milk listed above)
Form the scones as described in the blog post for Flaky Scones (or watch the video in the posts), adding the sliced rhubarb after the 1st letter fold when your dough is rolled out to a rectangle. Push the rhubarb pieces into the dough, fold, shape and cut into 8 wedges.