Line two baking sheets with parchment; set aside. In mixing bowl beat butter on medium to high for 30 seconds. Add 1/2 cup powdered sugar, vanilla, and 1/4 teaspoon salt; beat until well-combined. Beat in as much flour as you can. Stir in remaining flour. If necessary, chill dough 30 minutes or until easy to handle.
Heat oven to 400 degrees F. Shape dough in 1-inch balls, then pinch and shape balls into crescents. Place 2 inches apart on prepared baking sheets.
Bake 12 to 13 minutes or until bottoms are golden brown. Cool 1 minute on sheets. Transfer to wire racks to cool. Roll or lightly dust cooled cookies with powdered sugar. Makes 3-1/2 to 4 dozen cookies.
Prepare as above except increase powdered sugar to 3/4 cup. Reduce flour to 1 2/3 cups. Add cocoa powder and espresso powder with the flour. Bake 8 to 9 minutes. Lightly dust with additional cocoa powder.