Add flour, sugar, salt and cinnamon
First, add the all-purpose flour, sugar, salt and cinnamon in a bowl and stir the mixture repeatedly. You need to make sure that all the ingredients are properly combined before you proceed.
Add remaining ingredients
Now add the cup of milk, all the eggs and the vanilla extract to the bowl as you whisk the resulting mixture until it fully dissolves. Make sure there are no clumps in the end and the liquid is smooth. You can also use a fork to mix the ingredients if the whisk is not available.
Preheat a skillet
Preheat a skillet on medium heat until it reaches the temperature you require. Check by adding a drop of water, if it sizzles you can place the toast on it. Add a few drops of vegetable oil to the skillet. A good way is to grease it with a paper towel before you heat the skillet.
Dip bread slices and add to skillet
Take one bread slice at a time and dip it completely in the mixture. When you are done with one side, repeat the same process for the other side of the toast and then place it on the skillet. Do the same with all the slices of bread.
Remove when golden brown
When one side of the toast turns golden brown, flip it over and wait for it to reach the same colour. It is a good idea to put the french toast in the oven set to low so that they remain fresh as you cook the other slices.