Scones:
Sift together dry ingredients. Cut in margarine until crumbly. Add cream (1+ cups) as needed and gently gather together. Carefully fold in blueberries. Turn out on to counter and pat into a circle, 1 1/4-inch thick. Cut into wedges and place on a cookie sheet sprayed with cooking spray, with lots of room between scones. Bake at 400 degrees until lightly browned and a skewer inserted comes out clean. Cool slightly and drizzle with glaze.

Glaze:
Combine all ingredients in a microwave-safe dish and cook on high 30 seconds to 1 minute, until dissolved. Whisk smooth, and drizzle over scones. Note: These are very flaky and best served the same day they are made.