Preheat oven to 400° F.Place a 10-inch cast iron skillet in the oven to heat.Blend the eggs, milk, pumpkin, flour, pumpkin pie spice, vanilla, salt, and sugar together in a blender until smooth. Alternatively you can whisk the eggs and milk together in a bowl until blended and light yellow and then whisk in the other ingredients until smooth.Remove the skillet from the oven. Place the butter in the skillet and swirl it around until it melts.Pour the batter into the skillet and transfer the skillet to the oven. Bake 22-25 minutes until puffed up and golden brown. Remove from oven and serve (Dutch baby will start to fall within minutes of being taken out of the oven). Drizzle with yogurt and maple syrup and top with pecans. Dust with powdered sugar.