...it is damn sad, and I'm not sure if you can get it back. You've just got to move on to new dishes.
I mark the passing of two particular Lady Marmalade favorites. I used to make a vegetable stew with chickpeas, eggplant, tomato, and spinach. I learned how to make it in India, and it was a great dish to take to potlucks in college or to feed a crowd. It was a zesty, spicy, soul-satisfying main dish. Sometimes if I felt ambitious, I fried up some pooris (puffy Indian breads) to go with.
Somewhere along the line, I stopped being able to work my usual alchemy with the sauteed eggplant, the coriander and the cumin, the cooked-down tomato. I tried again about a year ago, but I just can't make it work anymore.
Same thing with caldo verde, the Portuguese soup made of potatoes, collards and chourico (or its Spanish variant, caldo gallego, the same thing, but with the addition of white beans or chickpeas). Some Portuguese-style cornbread (broa na fuba) on the side, that was a wonderful meal. A while ago, the potatoes started to taste/feel chalky, and I haven't been able to make it anymore.
*sigh* I suspect it's a matter of one's palate changing.