Step 1

Preheat your oven to 200°C (400°F).

Step 2

Sift and combine flour and ground cinnamon in a bowl.

Step 3

Add egg yolks, milk, lemon zest, and vanilla extract, then mix until you no longer see any lumps.

Step 4

In a separate bowl, beat egg whites and sugar into soft peaks.

Step 5

Add 1/3 of the beaten egg white into the milk and flour batter.

Step 6

Fold the egg whites to combine gently with the rest.

Step 7

Repeat until all the beaten egg whites have been incorporated with the rest of the ingredients.

Step 8

Place a small cast iron skillet (or any oven-proof pan) on medium-high heat on the stovetop and add half of the butter.

Step 9

Once the butter has melted, pour half of the batter, and arrange half of the apple slices on top.

Step 10

Place the pan on the stovetop and adjust the heat to medium-low.

Step 11

Once the sides of the German apple pancakes start solidifying, transfer the skillet to the preheated oven.

Step 12

When the pancake is cooked (but still not brown on top), take it out of the oven --- it generally takes 10 to 12 minutes.

Step 13

Generously sprinkle sugar on top, then place it back in the oven.

Step 14

Cook for 3 to 4 more minutes or when the top turns golden.

Step 15

Remove apfelpfannkuchen from the oven and serve with your favorite jam or ice cream!