My sourdough starter is almost 4 years old and it has a very strong, rustic taste (locals, I'm always happy to share - just email me from the link in my sidebar).
But after my sourdough got so weak and weary from neglect that it could hardly raise the roof on bread loaves, I have been careful to feed it at least weekly. Instead of throwing away the starter from the feeding, I make crackers. I tweaked this cracker recipe from Gina, who has some other great ideas for using the discarded sourdough.
I am pleased to have such easy crackers on hand for snacks and packed lunches. They're cheap and healthy, and I don't have to go to a store and throw away subsequent packaging to have them on hand.
1 cup "discarded" sourdough starter
1/4 cup butter, room temperature
1 cup whole wheat flour
1/2 tsp. salt
Combine sourdough starter and butter in mixing bowl. Add flour and salt and knead until smooth. Depending on the weather and the thickness of your starter, add more or less flour. Dough should be stiff. Cover dough tightly with a lid or enclose mixing bowl in a bag. Allow to sit at room temperature for 7-10 hours. Break dough into pieces and spread evenly on parchment or Silpat on a large baking sheet. Roll out to a 1/4" thickness or less, using a sheet of waxed paper between the rolling pin and dough. Use a knife or pizza cutter to cut into cracker shapes (I cut small squares). Bake at 350 for 30 minutes. Remove any crackers that are hard when you press on them. Hard crackers should break away from their partners easily. Turn oven down to 300. Return soft crackers to the oven for 10 minutes. Repeat pressing test, again removing hard crackers and returning soft crackers to oven. Repeat in 10 minute intervals until all crackers are hard. Cool all crackers and store in airtight container at room temperature.
Play with flavoring the crackers: sprinkle with an herb, more salt, or freshly ground pepper. Press it lightly into the rolled crackers. Once, I used part rye flour and added caraway seeds to the dough. I bet cheese or sesame seeds could be added.