Start your campfire or heat up your grill so that your heat source is ready. Let the flames die out and the charcoals turn grey prior to cooking your food.
Arrange enough of your coals in a circle to surround the Dutch oven without being touched by them. Carefully place your oven in the middle of the circle and preheat it while you get the batter ready.
Add your eggs, milk, and vanilla into a zip top bag and smoosh together thoroughly.
Combine flour, sugar, salt, and cinnamon in another zip top bag and mix.
Carefully add dry ingredients to wet ingredients bag and smoosh until completely mixed and your batter looks frothy.
Melt the butter in your preheated Dutch oven, making sure to completely coat the base of the Dutch oven.
Pour batter into the Dutch oven and level it out. Then place the lid over the oven.
With grilling tongs or a shovel, place a number of coals on the surface of the oven. Because we are baking our batter, we want to use the 3:1 ratio considered best for baking in a Dutch oven. This means we want three times as many coals on the lid as we need circling around the oven.
Cook Dutch baby with the coals for about 20 minutes, rotating the lid one quarter turn every five minutes.
Check to see if your batter is cooked. If so, remove the coals from the lid and take the pot away from the heat.
If you are topping your Dutch baby with warmed fruit, add it now, place the lid back on, and let sit for five more minutes.
Slice, serve, and enjoy!