Both!!! This is a trick question because I have answers to both:
What do you do when a recipe calls for brown sugar and you reach into the cabinet and yours is hard as a rock because you either a.) left it open and unsealed or b.) last used it in 2005 when you tried to bake once before ... The first thing you want to try is putting the brown sugar in the microwave. Try your best to measure out the amount you need so that you don't microwave more than you need. This should soften it right up because the only difference between white and brown sugar is that brown sugar has molasses mixed in - giving it the brown color. This also explains why dark brown sugar has a stronger molasses flavor to it - it has a higher concentration of molasses than the lighter version. So what you thought was bad brown sugar is now good again!
Brown sugar is a great ingredient that adds different flavor than white sugar, though you shouldn't be quick to substitute in every recipe. Brown sugar is a moister sugar, it will often make your baked goods more moist. Nutritionally, there isn't a big difference between the two. When you want to substitute, the amounts are equal - so 1 cup of white sugar = 1 cup of packed brown sugar. An important note - "packed" means that you use the back of a spoon to press the sugar down into the measuring cup until you have a completely packed down amount.
Today I decided to try making this Buttery Apple Torte and though the recipe called for white sugar I decided to try it out with brown sugar, because apples and that molasses flavor sound like they would go well together! It turned out delicious and completely moist!! We didn't even need to top it with ice cream or whipped cream - just the confectioners' sugar (for looks for than anything else).
6 TB plus 3 TB butter (1 stick plus 1 TB)
4 Macintosh Apples - peeled, cored and sliced
3/4 cup wheat flour
1/2 tsp. baking powder
1/2 tsp. salt
1/4 tsp. cinnamon
Dash of nutmeg
2 whole eggs, plus 1 egg yolk
1 tsp. vanilla extract
1 cup packed dark brown sugar
1/2 tsp. grated lemon zest
One squeeze of lemon juice (probably just a TB)
4. In a larger bowl, beat the whole eggs and the egg yolk together (or whisk). Add the 6 TB of melted butter, vanilla, brown sugar, lemon zest and lemon juice. Mix until blended together well.
6. Bake for 30 minutes. Take out of the oven and put on a wire cookie rack to cool for 5-10 minutes, then you can take the cake out of the pan and continue to cool it on the rack. Hint: Put a large plate over the top of the cake pan, invert the pan so that the top of the cake is now on the bottom of the plate. Then put the cooling rack over the plate (and bottom of the cake) and invert again. Now you have the cake sitting right side up on the cooling rack!
*Note: I thought this dessert might actually be a good brunch item as well - it was definitely sweet, but not over the top and a small slice with coffee and some fresh berries on top would be perfect!