Mix together dry ingredients in a medium-sized bowl. Beat together eggs, milk and vanilla then add to dry ingredients and combine. Heat a large skillet or griddle. Add butter to skillet. Dip each slice of bread in egg mixture and transfer to skillet. Cook, flipping once, until egg mixture is set and browned on both sides. Continue adding butter to the skillet, as needed, as you cook more French toast. Serve with butter and syrup, or your favorite French toast toppings.