Preheat oven to 350°F. Cream together the butter and sugar for 1 minute. Mix in the eggs, one at a time. Stir in the vanilla and peppermint extracts. Whisk together the flour, baking powder and salt. Add to the wet ingredients and mix on low speed. Using a small cookie scoop, spoon 1-inch dough balls into bowl of sugar and lightly roll to cover.