Make the soufflé pancake batter:

1. Separate the egg whites and egg yolks into separate mixing bowls.
2. Into the egg yolks, add milk, vanilla extract, and lemon zest. Whisk until combined.
3. Sift in flour and baking powder. Whisk until smooth and no dry flour remains. Set aside.
4. Into the egg whites, add vinegar or lemon juice. Beat with a hand mixer on medium speed until frothy. Gradually add sugar.
5. Increase speed to medium-high and beat until stiff peaks form.
6. Fold ⅓ of the stiff meringue into the egg yolk batter using a rubber spatula. Gently fold until no streaks remain.
7. Add the remaining meringue and fold until combined. Do not overmix, or the batter will deflate.
8. Transfer the batter into a large spoon, cookie scoop, or piping bag fitted with a large round tip.

Cook the pancakes:

1. Heat a large nonstick pan over low heat and lightly grease with oil. Wipe away excess oil.
2. Portion the batter into the pan, making 2 to 3 pancakes. Keep the batter tall for best results.
3. Cover the pan with a lid and cook for 7-8 minutes until golden brown on the bottom.
4. Gently flip the pancakes, cover, and cook for another 5-6 minutes until golden brown and fully cooked.
5. Serve immediately with whipped cream, berries, powdered sugar, or maple syrup.

Optional sweetened whipped cream:

1. In a mixing bowl, combine heavy cream, sugar, and vanilla.
2. Whisk by hand or use a hand mixer until firm peaks form.
3. Keep refrigerated until ready to serve.