The secret has always been frozen chopped spinach. Absurdly cheap, doesn't go bad, blends/melts away into EVERYTHING! (Pasta, soups, beans for tacos, whatever).
I will note, the hard limit is you can't actually use it in a salad... but hey, tradeoffs
Yeah, I don't think you are going to taste much of that in a stew (which is by definition a soggy mush). As noted you don't want to use this for anything fresh where mostly fresh vegetables will be superior.
