Preheat the oven to 425°F (220°C), or 200°C if using a fan oven. And place a 10 inch oven proof skillet in the oven as it preheats.
To make the batter, in a jug of a blender, combine milk with eggs, flour, lemon zest, vanilla extract, nutmeg, and salt. Blend for 20 seconds, stop and scrape the sides of the jug with a spatula, then blend again for 10 more seconds.
Remove the skillet from the oven (using mitts), and place on a trivet. Add the butter to the hot skillet, and let it melt.
Using a pastry brush, brush the butter on the sides of the skillet too.
Pour the pancake batter in the center of the hot skillet, then return to the oven.
Bake for 18-20 minutes or until puffed and golden brown.
Remove from the oven, garnish with fresh fruit, fruit compote, or/and fresh whipped cream, a drizzle of honey or maple syrup, a sprinkle of powdered sugar.