Melt the butter and shortening in a small saucepan, stirring to combine; remove from the heat and set aside. Whisk the flour, baking powder, salt and sugar in a large bowl.
Whisk the eggs, milk, chocolate syrup and vanilla in a large liquid measuring cup or a separate bowl. Whisk the egg mixture into the flour mixture until combined. (The batter will be slightly lumpy.) Whisk in the butter mixture until combined.
Preheat the oven to 250 degrees F. Preheat a waffle iron and spray with cooking spray. Ladle some of the batter into the waffle iron to within an inch of the edge (1/3 to 1/2 cup batter, depending on your waffle iron); cook until crisp. Transfer the waffle to a baking sheet and keep warm in the oven. Repeat with the remaining batter.
Divide the waffles among plates. Dust with confectioners'sugar and top with berries and/or chocolate syrup.