Preheat grill to 425F. Divide melted butter evenly between 2 aluminum pie tins and swirl around to coat the tins well.
In a large bowl, whisk together milk, flour, eggs, and nutmeg, leaving batter slightly lumpy.
Divide batter evenly between the 2 greased pie tins, then place each pie tin in on the grill. Grill uncovered for 12-14 minutes, or until golden brown and fluffy.
Carefully remove pie tins from grill and slide pancakes onto two plates. Top with blueberries, strawberries, or other berries, and powdered sugar and serve immediately.