In a medium-sized mixing bowl, whisk milk, eggs and vanilla extract together.
Sift the flour into another bowl. Add baking powder, sugar and salt and stir slightly.
Put the butter into the 8 or 9 inch non-stick skillet with a heat proof handle and melt it on a medium-high heat. Once the butter is melted and starts to foam, pour the butter into the milk mixture and stir.
Pour the liquid ingredients over the dry and whisk gently.
Pour this mixture onto the still hot skillet and place it in the oven. Bake for about 20 minutes, until the pancake looks well browned and puffy. (It will deflate once it cools down)
Spread Nutella over the pancake and top it with strawberries and blueberries.