Combine 1/2 cup sugar and cinnamon in a small mixing bowl; mix well, and set aside.
Combine eggs, milk, remaining sugar, and salt in a medium mixing bowl; mix well. Add flour, and beat with a wire whisk until smooth. Stir in lemon extract, mixing well.
Dip rosette iron into hot oil (375°); drain off excess oil. Dip hot iron halfway into batter; return to oil, and cook 30 seconds. Buñuelo will slip off rosette iron after 10 to 15 seconds. Turn buñuelo occasionally. Remove with slotted spoon; drain on paper towels. Sprinkle with reserved sugar-cinnamon mixture. Repeat procedure with remaining batter.