The altered palette of produce options in Germany endlessly charms and frustrates me. Butternut squash, ubiquitous in America and its recipes, is an elusive quarry, while the once-exotic quince fills baskets everywhere. Suppengrün is an item I'd never even guessed at before coming here, but stumble across constantly at my local organic supermarket or the many Vietnamese-run fruit & vegetable shops.

A tidy packet consisting of a quarter of celery root plus greens, a length of leek, and two lumpy carrots, Suppengrün provides you with the basics for stock-making in the amounts you need. (In some weird way I've always thought of Suppengrün as Germany's answer to the Italian odori that Nigella Lawson writes of.) Chopped up with some parsley, herbs and onions, it makes a perfect dark and aromatic vegetable broth, reviving by itself or providing a flavourful base for soup.

Vegetable broth

(This is just the sort of recipe I imagine no-one would need, except I did, and so perhaps you would like it too...)

• 1 Suppengrün or components thereof*, washed, trimmed/peeled and coarsely chopped
• 1 large yellow onion, peeled and coarsely chopped
• 5 large garlic cloves, peeled and trimmed
• 1 bunch parsley (6-8 stalks)
• 1 bay leaf
• 4 cloves
• 1 small pinch Herbs de Provence
• 1/2 C dry white wine (optional)
• 1 tablespoon olive oil

* If you can't find celery root, substitute a stalk of celery.

Add oil to a large, heavy-bottomed soup pan over high heat. When the oil is hot, add all ingredients and let them brown, stirring every couple of minutes, for a total of 10-15 minutes. Add the white wine, stirring thoroughly, and let cook for a few minutes. Then add 2 liters/2 quarts cold water. Bring to a boil, then reduce to a simmer and let cook for 30 minutes.

Use a slotted spoon to remove the solids, and pour the broth through a fine-meshed strainer. Serve hot, garnished, if desired, with a thin slice of lemon and some chopped chives. (You can also just serve the vegetables as part of the soup, or separately, or puree them into the broth with an immersion blender or food mill, as you like.)