Combine milk, eggs, melted butter, flour, cocoa powder, brown sugar, baking powder, salt, and vanilla extract in a blender. Blend for 1 minute or until smooth. Let sit for 30 minutes.
Melt 3 tablespoons butter in a cast iron pan over medium heat. Combine 4 tablespoons sugar with cinnamon and nutmeg and sprinkle on top of butter. Arrange pears on top. Sprinkle remaining 2 tablespoons sugar on top and bring to a simmer over medium heat.
Remove from heat and slowly pour pancake batter evenly on top. Bake chocolate German pear pancake for 15 minutes. Reduce oven temperature to 375 degrees F and continue to bake for another 10 minutes. Remove from oven and serve warm with whipped cream if desired.