Direct from the campfire, This is one of Johnny's best and goes great with a dollop of whipped cream or a scoop of ice cream. He claims that they wrote a book about him called "Johnny Appleseed", but that's another story...
Preheat oven to 425°F Place oven rack on the middle rack of your oven. In a small bowl, combine sugar and cinnamon. Set aside.
In a large bowl, combine flour, milk, eggs, salt, and vanilla extract. Beat until batter is smooth and set aside.
In a 8" or larger cast-iron frying pan over medium heat, melt butter, tilting pan to cover sides. Add apples and sprinkle with sugar and cinnamon mixture. Stir and let cook for 5-7 minutes to slightly cook the apple slices. Add raisins if using and remove from heat.
Pour the batter over apples into baking pan. Place pan in oven and bake 20 minutes or until puffed above sides of the pan and lightly browned (it may puff irregularly, but this is normal). Remove from oven.
Remove pancake from the baking pan by flipping upside down onto a serving platter so that the apples are on top. To serve, cut into serving-size wedges and transfer to individual serving plates. Note: Once out of the oven, the pancake will begin to deflate, but that is okay.