I really, really just want to change the color of my ingredients!

All I can find when googling is instructions for making custom and new ingredients though, and try as I might to piece together only the pieces of information that I need, I am just lost. I couldn't find the actual files that held the ingredient images either, aside from custom ones I downloaded from omedapixel to try and figure out how they worked. If I change the color of those, obviously it would work, but she only has a few that she changed so I cannot create more.
I even failed to just change the names of ingredients when I thought that would be easier using an STBL file with a key that followed Gameplay/Excel/Ingredients/Data: and then the Ingredient_Name.

If anyone could help me with the first issue, or even the second issue if you're feeling generous, I would be super grateful! I've been struggling with this for weeks.

You mean the textures for ingredients' 3d models, right? Found them in FullBuild2 package (in GameData\Shared\Packages). Examples:
onions_0x431aaec3e6a9e727
cheeseWheel_0x7edfa869781fec93
watermelonSlice_0x1fddd1266f86ade7
lifefruit_0x836cf2ad2e2658bb
burgerMeatGround_0xe972bc607eb7b48a

In addition to the above, if you need to find textures that aren't named - the way you'd go about it would be cloning the food using a dummy OBJD (a term you may have seen in the discussions about making custom food/ingredients) with renumber unticked. This would get you a package including the textures, you could simply delete the rest.

To rename them, you'll want to override the same exact strings - find their GUIDs using S3SE, then make sure the STBL in your package has an ID starting with 00 (for English) and ending with 00000000 (a quirk of STBL load order, this makes sure your changes load last after the master STBL).