Roll out the shortcrust pastry and prick with a fork. Leave to rest while you prepare the filling.
Drizzle a saucepan with 2 splashes of oil and throw in the finely chopped onion and garlic. Before the garlic browns, add the Carnevale and stir until well mixed with the onion and garlic. Pour in boiling water and cook over a medium flame until the water has been fully absorbed.
Spoon the filling onto the pastry and roll. You could pour coffee (liquid) over the top to give it more colour. Preheat the oven to 175ºC and bake for 30 minutes.