Discarded sourdough starter

Sarah, for best results I wouldn't try to bake with old discards. Absolutely not with discard from a starter that has not matured yet. Also, your starter might be ready. Try building a dough with your lateral discard. Use 15% starter to flour. And see how it performs.

I just posted my adaptation of the pancakes /waffles made using the spent starter: https://food52.com/recipes/52167-sourdough-pancakes-or-waffles-using-starter-left-over-from-feedings?preview=true
I made them this morning - a Friday! Putting them on the two burner griddle that came with my stove made it so, so easy. ;o)

Sarah, what hydration is your starter? And what kind(s) of flour are you feeding it? ;o)

I called King Arthur Flour direct line years ago when I got my first starter from them....it didn't seem right to "throw away" all that starter..Which it exactly what the routine calls for....
So stead, I treated it like a separate batch and made my own pizza dough ( eyeball it...add flour, olive oil, Italian seasonings....mix it up, leave in fridge a day or so..YUMMM.... OR use it for English muffins ( got recipe from CHOCLATEANDZYCCHINI or KA)

MANY WAYS TO USE IT!!
Also, do try yo feed it regularly, however unless a terrible smell is associated with it, th slime green color means nothing ...just baby it along and I will do just fine.

I just began a starter maybe 8 or 9 days ago so I'm in the same boat as you (using the Tartine no. 3 method), and used my discard yesterday for this focaccia using Spelt and AP flour and topped with zaatar -- turned out great!

bojongourmet.com/2009/10/quick-and-dirty-sourdough-focaccia/

Helpful discussion in the comments about halfway down this page: Rivka and I, on using starter in more conventional loaves. https://food52.com/recipes/4022-buttermilk-oatmeal-bread

I bake Tartine Bread or similar artisanal boules every week, so I have a fair bit of spent starter on hand. I like to add it to my multigrain sandwich breads, using these simple rules for adapting:

1. Start with a bread recipe that has been tested using mass (gram or ounce) measures, not volume. I adapted my Buttermilk Oatmeal Bread recipe to provide metric measures and to use instant yeast (easier). https://food52.com/recipes/40561-buttermilk-oatmeal-bread-updated

2. Figure out how many grams of water and how many grams of flour are in your starter. If you have a 100% hydration, you have equal amounts of each.

3. Substitute liquid and flour ratably. I have found that there is a limit to how much starter can be substituted, as the yeast needs fresh flour to feed on during the two proofing stages. I typically don't go above 1/3 total liquid + flour.

4. I use yeast, but not as much - as little as 1/4 teaspoon of instant for a long, slow ferment, up to about 1 1/2 teaspoon, with less on warm days. You get a better loaf - texture, not just flavor - if the dough doesn't proof quickly.

5. Bake according to base recipe instructions.

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Taking this in another direction: I also use my spent starter to make a basic hybrid sandwich loaf. I feed it a bit for a few hours before starting, adding what is necessary to get the total up to 260 grams. Stir 250 grams starter with 210 grams water; add 1/2 teaspoon instant yeast and 375 grams flour (usually AP with a bit of whole wheat and rye, total about 40 grams) and stir. Add 7 grams salt and stir. Let sit for twenty minutes. Knead for 10 minutes with dough hook on mixer. Turn into oiled bowl, let rise for 1 - 4 hours depending on temperature, how much yeast, etc., until doubled. Shape and put in loaf pan lined with a parchment sling. Let rise until the top is one inch above the rim of your loaf pan, 1 - 2 hours, again depending on conditions. Do not let it over-proof. Bake at 400 degrees for 40 minutes. Let cool for at least an hour before slicing. ;o)

THANKYOU Antonia!!! I am looking forward to the jam sandwich.... Also really good are waffles with vanilla ice cream and maple syrup.

I don't really have a recipe, I just eyeball it... But put the 1-1.5 cups discard in large bowl. In separate small bowl or liquid measuring cup, put about a up of liquid... I use water for general use, milk if I'm thinking of going sweet. If the latter, I also add about 1/3 c sugar, and some melted butter. My yeast needs proofing, so I add it to this liquid and wait for it to he foamy before I add liquid to discard. If you have the instant yeast, you can skip the separate bowl and just add to discard to make slurry. Then about two cups flour and 1/2 tbsp salt. Mix all together ( just until incorporated). Should be really sticky and shaggy. I hope this helps!!! Let me know if you have more questions :)

Oh, and I have this bookmarked, but haven't tried yet: http://cooking.nytimes.com/recipes/1018025-sourdough-pancake-or-waffle-batter

So when you half it and feed it, you are saving up the "toss" half? It SEEMS to me like you could use that to make bread! I say try it, the worst that could happen is you waste a few cups of flour, right?

I save all the discard in a container in fridge. I use it to make no knead bread (1-1.5 cups discard in bowl. Measure about 1c liquid in jug with some sugar and 1/2 tbsp yeast... Let sit until yeast foamy, then mix with discard until you have a "slurry" , then add about 2 cups flour, sprinkle 1/2 tbsp salt over and mix all together to get fairly sticky, shaggy dough. Let rise about 2 hours... Maybe a quick knead at 1 hour to de-gas). You can shape into loaf and let rest while you preheat to 450, or use for pizza, hand "pies", calzone, cinnamon buns, soft pretzels etc....