Spread bacon on a foil-lined broiler pan. Bake at 300° F for about 30 minutes. In a small container, mix together with a fork the brown sugar and mustard, until crumbly. Take the pan with the bacon out of the oven and dispose of the grease when cool.
Evenly distribute the brown sugar mixture by hand over the bacon and return to oven; bake 20 to 30 minutes. Remove from oven and cool.
Cut bacon into 1- or 2-inch pieces and serve. Do not stack pieces when serving.
Servings: 25