Dark Brown Sugar
No need to buy brown sugar in a plastic bag. You can easily make your own in advance or as needed. When needed in a recipe that gets a lot of mixing, I just use slightly less granulated sugar than the recipe requires and toss in the molasses. When I make my favorite chocolate chip cookies, I mix the brown sugar in the same bowl that I then mix the cookies in. Granulated sugar is easier to store and measure than brown sugar.
1 cup granulated sugar
1 tablespoon molasses
In a bowl, mix together sugar and molasses (takes a lot of mixing). A stand mixer makes this much easier. Or a food processor (but messier cleanup in this case).
Store in an airtight container.