Veg Scrap Soup
The base for risottos, noodle dishes, and more
There’s a reason Scraps is named so — this veg scrap soup base is something I’ve been making for years, and it was one of the first things I wanted to publish when I launched my newsletter at the start of the year. Once again, it’s not really a recipe, but more of an ethos, or an idea. A way of using every last bit out of every last bit.
Essentially, as I go about my silly little kitchen, I make sure to put all my vegetable peels and scraps in a freezer bag. This includes everything from a wrinkly clove of garlic to carrot and potato peels. The ends of an onion, and onion skins, often go in. Spring onions, sprigs of rosemary or thyme. Ginger is good, too — some people peel ginger with a teaspoon because they saw it on a Buzzfeed video in 2014, and I love that for them. But I find the outer layer of ginger quite woody and unpleasant, so I still use a sharp knife (this also means you can cut a neat rectangle of ginger, which is then easier to slice and mince). Mushrooms are also a godsend in this stock.
Then, when the bag is full, I take out and start cooking.
This is a vegetarian recipe but I often add a chicken carcass from a roast dinner into the mix when I have one, too. Bones contain gelatine, which will make your stock more luscious and rich as it cooks. You can skip it though.
The first thing to note is that you start cooking from frozen. Lay the scraps onto a baking sheet and drizzle with olive oil. We’re just thawing them out a little at this stage. Don’t worry about crowding the pan, either — crowding will cause them to steam, which is fine.
After 10 minutes or so, take the scraps out the oven. Now they’re less frozen, we’re going to roast them, but they need a little help. I add a tablespoon of miso paste to a cup or so of hot water and pour the miso-mixture over the scraps. With your hands, massage the miso in slightly. The sugars in the miso will caramelise as the scraps roast, which will give them a richer, deeper flavour. You could also add seasonings, like garlic or onion powder, if you wish. Put the tray back in the oven for 20 minutes or so. I’d suggest a medium-high heat.
Keep checking them; you want to see things crisping up and looking roasty (see how the edges are crisped and browned, with some nice sticky baked-in bits on the tray?). The more roasted everything is, the more flavour you have. I had some sweet potatoes in my bag, and they go kind of custardy which brings a nice starchy texture to the overall soup, and old lemon halves would be great roasted too.
On the day I made this stock, I was in and out the house in meetings, so rather than cook this in a pan, I did it in the slow cooker. I added the scraps, plus a pyrex of water and a couple of wedges of lemon. I did it on a high heat for 30 minutes then knocked it down for a whole afternoon.
Every now and then, grab a ladle and taste it. What you’re looking for will vary — I always prefer a seasoned, flavoured stock and the miso adds a rich savouriness that can sometimes be a bit salty. So a dash of lemon is good in here to cut through it. The onion skins will add a nice chestnuty colour to the stock, too.
It’s done when it’s done — keep tasting it and figure out what it needs. I’d aim for 4 hours total, but if you’re using bones or a carcass, I think 8 is preferable (overnight is even better). I strain it, sometimes twice, and decant into jars. This stuff freezes really well, too — but I’ll be honest, I prefer making it to order rather than stuffing my freezer with bags of the stuff.
As for what to do with it? I use it in everything. It’s a good base for noodle soups. You can use it in a risotto, too (cook your raw aromatics, like diced onion and carrot, then add some wine, and when the wine has cooked off, then you add in this stock). It makes a good soup base. Last week, I was in the mood for something light and bistro-y, and saw this recipe for summery beans and greens with breadcrumbs in the New York Times.
I decided to do my own version; a finely diced onion, sweating down in olive oil with two smashed garlic cloves. I sliced four spring onions into diagonal stumps and added them in, too (rather than have them cook down, I wanted to cook off the onion-y taste but retain the green, clean, and crunchy aspects). I added in a diced sweet potato, and some drained butter beans. Then the stock. I brought it to the boil then simmered for 45 minutes.
Once it came off the heat I added in finely sliced rainbow chard (grown on the balcony!) — they wilt in the residual heat and retain a grassy crunch. I finished it with some chicken-skin breadcrumbs from the last issue, and a drizzle of good olive oil. The result was fresh and light but also incredibly filling.
Stray thoughts:
You really could put almost anything in this stock, but avoid broccoli, cabbage, any brassica. Ditto aubergines, or anything with a high water content.
Tomatoes are a no, but you could add tinned tomatoes to the finished stock and whip up a vegetable curry.
Squash would be excellent, the skins are full of vitamins.
In terms of herbs, skip anything grassy (basil, corinader) as they get a bit slimy when overcooked. Parsley stems would be fine, but stick to woody options if you’re going to put them in the stock.