made from scratch

I'm on a mission from Dog to learn to make more meals from scratch. But that leads me to an existential question:

What exactly is 'scratch'?

(Yes, I put my question marks outside of my quotation marks. If the quotation isn't a question, I think the placement of my mark ought to specify so, even if it isn't proper grammar. I tear the tags off pillows, too.)

As an example, we love green bean casserole. My family grew green beans as a kid, and they are one of a handful of green things I can unquestionably recognize. You can buy it at the store in a pre-made box where you just add water. Sometimes you can even buy it ready-made at the deli counter. T's mother makes it the 'traditional' way -- that is, with a can of Campbell's Cream of Mushroom Soup. Is that 'from scratch'? It gets points, of course, because Mom made it, but take a look at the ingredients:
water, mushrooms, vegetable oil, enriched wheat flour, salt, cream, corn starch, whey powder, soy protein isolate, monosodium glutamate, tomato paste, calcium caseinate), yeast extract, spices

Mmm, our good friend MSG. Not exactly what I would call wholesome. The ingredients in the French's Fried Onions are relatively benign, by comparison:
palm oil, wheat flour, onions, soy flour, salt, dextrose


But neither of these things are 'from scratch.' You could make your own soup, and your own fried onions. But that then begs the question -- how far must you go for it to really be from scratch? If you make your own fried onions, do you have to grind the flour yourself? Grow the wheat from seed?