Scottish Scones - cooking recipe

Ingredients

2 c. all-purpose flour
2 tsp. baking powder
1/2 tsp. baking soda
3/4 tsp. salt
3 Tbsp. sugar
1/4 c. plus 1 Tbsp. butter or margarine
1/2 c. currants
1 (8 oz.) carton sour cream
1 large egg, separated
1 tsp. sugar
1/8 tsp. ground cinnamon

Preparation

Combine first 5 ingredients in a large bowl; stir well.
Cut in butter with pastry blender until mixture is crumbly.
Stir in currants.
Combine sour cream and egg yolk, stirring well; add to flour mixture, stirring just until dry ingredients are moistened.