In a large mixing bowl, whisk together the eggs, milk, cinnamon, and sugar until well combined.

Grease a large skillet or a griddle with butter or non-stick cooking spray. If you're using a campfire, make sure you have a grill grate set up over the fire for cooking.

Dip each slice of bread into the egg mixture, ensuring both sides are well coated.

Place the coated bread slices onto the skillet or griddle. Cook over the campfire for about 2-3 minutes on each side or until golden brown and the egg mixture has set.

Once cooked, remove the French toast from the skillet and serve warm. If desired, top with maple syrup, powdered sugar, or fresh berries for added flavor.

Repeat the process with the remaining bread slices and egg mixture, adding more butter or spray as needed to prevent sticking.