How many times have you gone to open up a bag of brown sugar only to find that it has turned into a brown brick? If you make your own you will always have fresh brown sugar on hand and it will always the color that the recipe calls for (light or dark.) Bonus: You will save money and need less storage space to store your sugars.
1 C white sugar
1-2 Tbsp molasses have
Mix the molasses with the brown sugar until it is thoroughly incorporated. You can do this most simply with a fork, but if you can use an electric beater or food processor it will go lightening quick.
For recipes calling for light brown sugar, use one tablespoon molasses. For recipes calling for dark brown sugar, use two or more tablespoons of molasses.