In a large bowl, whisk together the flour, sugar, baking powder, pumpkin pie spice, orange zest, and salt.
In a smaller bowl, whisk together the milk, orange juice, pumpkin, eggs, and vanilla.
Stir the milk mixture into the flour until just combined with no streaks or lumps.
In a large skillet, place about 1 teaspoon butter over medium-low heat. Once thoroughly heated, add about 1/4 cup batter. Flip to the other side once the top begins to set with bubble formation and the bottom is golden. Do not flatten with spatula. Cook the other side until golden. Repeat with remaining batter, buttering the skillet as needed.
Serve immediately topped with orange slice, chopped pecans, butter, and maple syrup if desired.