Sift together dry ingredients; cut in butter till like coarse crumbs.
Mix egg and milk; add all at once; stir just to moisten.
Use dough to prepare the following rolls, then bake at 450° for 25 to 30 minutes.
Add ¾ cup sugar to 1 cup water; simmer 5 minutes.
Pour into 9x9x2-inch pan.
Roll 1 recipe Plain Shortcake to 12x8-inch rectangle.
Brush with 1 tablespoon melted butter.
Top with 1 cup sliced fresh strawberries and 2 cups finely diced rhubarb.
Sprinkle with ⅛ cup sugar.
Roll as for jelly roll, starting at long side; seal edge.
Cut in 12 slices; place atop syrup, cut side down.
Bake.
Serve warm.
