Preheat oven to 425°F. Grease a muffin pan with butter or nonstick spray or line with paper baking cups.
Whisk together flour, baking powder and salt. Set aside.
In a large bowl, cream together butter and 1 ¼ cups sugar until very light and fluffy, about 10 – 15 minutes, scraping down the sides of the bowl often. Add eggs one at a time, beating well after each addition.
Add half the flour mixture and beat until just blended. Beat in buttermilk, then add remaining flour mixture and beat until blended. Gently fold the blueberries into the batter.
Spoon batter evenly into 12 prepared baking cups. Sprinkle with remaining 2 tsp sugar.
Place pan in oven and immediately reduce heat to 375° F. Bake for 30 minutes or until muffin tops are golden brown. Cool in pan for 5 minutes. Move to wire rack to cool completely.
