Agro-dolce, in Italian, literally translates to 'sour-sweet' and this is recipe that I learned when I was in Rome, cooking cippolini onions this way. I figured the mixture of the honey and vinegar would counter the strong flavor of the black Spanish radishes.
I was right! This was a delcious side dish or condiment tonight...and all you need: whatever you want to cook agro-dolce, some butter, olive oil, vinegar, water, honey, salt, and an herb of your choice.
Scrub and slice the black radishes; slice cleaned leeks into coins. Cook the radishes and leeks with a pat of butter and a splash of olive oil until they begin to brown.
Deglaze the pan with rice vinegar. Add water and continue to simmer until the radishes are fork tender. Season with pink Himalaya salt and fresh chopped dill. Stir in honey.
I served this with steamed forbidden rice and a beer-poached salmon with shitake mushrooms and asparagus.