Preheat shortening or oil in the deep fryer to 190 °C (375 °F). Line a baking sheet with paper towels.
In a bowl, combine flour and baking powder. Set aside.
In another bowl, beat eggs, lemon zest and sugar with an electric mixer for about 1 minute or until frothy. Add ricotta and mix thoroughly. With a spatula, gently fold in dry ingredients until batter is just moistened.
With a 15 ml (1 tablespoon) ice cream scoop, gently drop 8 balls of batter at a time in hot oil. Beware of splattering. Fry for 2 to 3 minutes or until doughnuts are golden brown. Drain on paper towel. Let cool.
To serve, generously dust with icing sugar.
Doughnuts are best eaten at room temperature and ideally the same day.
Recipes with the "Healthy Pick" stamp have been evaluated by a registered dietitian member of the Ordre professionnel des diététistes du Québec.