Step #1 In a bowl, baking powder, cinnamon, mix flour, sugar, & salt.
Step #2 In another bowl, pumpkin, beat milk, egg yolks, & butter to mix.
Step #3 Stir into flour mixture until evenly moistened.
Step #4 In another bowl, with a mixer on high speed, beat egg whites until soft peaks form.
Step #5 Gently fold egg whites into batter just until incorporated.
Step #6 Place a nonstick griddle or a 12-inch nonstick frying pan over med-heat/flame (350º); when hot, coat lightly with oil & wipe dry with a paper towel.
Step #7 Pour batter in 1/2-c portions onto griddle, spreading slightly with the back of a spoon, & cook this until pancakes are browned on the bottom & edges begin to look dry, about 3 mins; turn with a wide spatula & brown other sides, 2 to 3 mins longer.
Step #8 Adjust heat as needed to maintain an even temperature.
Step #9 Serve pancakes as cooked, or keep warm in a single layer on baking sheets in a 200º oven up to 15 mins.