Preheat the oven to 350 degrees Fahrenheit.

Line 24 regular sized muffin tins with paper liners; set aside.

Combine flour, baking powder, and salt in a medium sized bowl. Using a wire whisk, whisk together until completely combined.

In a large bowl, cream shortening and sugar.

Add egg whites, and mix on high speed for 5 minutes, scraping the sides of the bowl occasionally.

Beat in vanilla.

Reduce mixer speed to lowest speed, and add 1/3 of the flour mixture. Mix until just combined.

Add half the milk, then another 1/3 of the flour mixture, the remaining milk, and then the remaining flour mixture.

Scrape the sides of the bowl, and mix until just combined, taking care not to overmix.

Divide batter evenly among muffin tins.

Bake for 20 minutes, or until inserted toothpick comes out clean.

Allow to cool completely.

Cream margarine in a large bowl, using an electric mixer.

Add 2 cups of powdered sugar, cinnamon, whipped topping, and salt.

Beat on high, until smooth and creamy.

Add remaining powdered sugar, and mix until smooth.

Using an apple corer, or a small paring knife, remove the center of each cupcake, creating a “well.”

The “well” should reach almost to the bottom of the cupcake, but not all the way, and should be one inch in diameter.

Drop a small teaspoon of blueberry pie filling into each cupcake’s “well”.

Pipe a swirl of cinnamon frosting on top.

Garnish with fresh blueberries.