Preheat the oven to 325°F. In a large bowl, whisk together the milk, eggs, sugar, vanilla, and butter until the sugar is dissolved.
Add the flour and whisk until smooth.
Pour the batter into a cast iron skillet or pie pan.
Now add your favorite fruit or flavoring (see below).
Bake until the clafoutis is beautifully puffed and golden, 35–40 minutes.
Serve immediately.
Clafoutis Variations:Concord Grape Clafoutis: Once the batter is in the skillet, scatter 2 cups slightly crushed Concord or other black or red grapes on top.Cherry Clafoutis: Scatter 2 cups pitted cherries onto the batter once it's poured into pie plates.Pear Clafoutis with Pear Eau de Vie: Core 1 ripe pear and cut into pieces.
Pour the batter into the skillet and top with the pear pieces.
Bake.
Drizzle with 2 tablespoons eau de vie and serve immediately. Milk Chocolate and Hazelnut Clafoutis: Melt 1 cup chopped milk chocolate in a large mixing bowl set above a simmering pot of water. Fold in the clafoutis batter until smooth and fully incorporated.
Pour into a skillet or pie plate, sprinkle with 1/4 cup coarsely chopped hazelnuts, and bake.