Prepare the doughnut dough. Sift the flour and baking powder together in a medium-sized bowl. Add the sugar, eggs, Ricotta, vanilla and lemon zest. Beat the mixture thoroughly until it becomes smooth.
Heat the vegetable oil in a pot over medium-high heat. Using a teaspoon (15 mL), form small balls of dough and drop them gently into the oil. Deep-fry for around 3 minutes per side, or until the doughnuts become golden. Place the doughnuts on paper towel to dry.
Prepare the chocolate sauce by melting all ingredients in a double-boiler, stirring continuously until the mixture becomes smooth and shiny.
Let the doughnuts cool for around 5 minutes before serving with chocolate sauce.
