Line 18 regular-sized muffin cups with paper liners.
In a medium bowl, combine flour, baking powder, baking soda, cardamom, and salt.
In a large mixing bowl, combine sugar, butter, and orange zest. Beat until light and fluffy.
Beat in the ricotta.
Beat in the egg, orange juice, and orange extract.
Add the dry ingredients to the mixing bowl, and beat until just blended.
Divide the batter evenly among the prepared muffin cups, filling almost to the top of the paper liner.
Sprinkle the hazelnuts evenly over the muffins.
Sprinkle the muffins with a pinch of sugar.
Bake at 350 degrees until the muffins are light golden brown on top, about 18-22 minutes. Allow to cool.