In a bowl, whisk eggs with milk, zests and vanilla. In another bowl, mix flour with sugar. Gradually add the liquid preparation to the dry ingredients. Whisk until obtaining a smooth pastry.
Butter eight ramequins of a capacity of 250 ml (1 cup) or a pie plate of 25 cm (10 inches). Divide the preparation into the ramequins up until a third of the height or pour into the pie plate.
Oven bake ramequins for 15 to 17 minutes. For the pie plate, cook for about 20 to 25 minutes.
Remove from oven and cool down. When serving, spread icing sugar with a sieve, if desired. Garnish with fruits.