A Culinary Cycle to Reduce Waste

Trimmings from a Vegetable Roast Become a Stock that’s Integral to a Soup in These Three Recipes

Credit: Courtesy Shutterstock

This story originally appeared in the Santa Barbara Green Guide 2025/26,
a collaboration publication between ‘Santa Barbara Independent’ and ‘Bluedot Living‘.

Thinking creatively about how to use every part of your vegetables is both economical and sustainable, helping to reduce food waste while maximizing flavor and nutrition. You can create rich, flavorful stocks or add extra layers of depth to soups, stews, and sauces by repurposing vegetable scraps that are often discarded — like skins, stems, and leaves. You can use the stock immediately or freeze it in portions for future meals, ensuring you always have a homemade base on hand. These three recipes will take you through the process.

RECIPE: Vegetable Roast With Tahini Yogurt Sauce

One-pan dishes such as this are great for busy weeknights when you want to avoid having masses of washing up after cooking dinner. I make these easy vegetable roasts throughout the year with the seasonal vegetables I have on hand. This version celebrates autumn with glorious, sweet, earthy cruciferous vegetables and jewel-toned squashes. I use zucchini and patty pan squash in the summer and often add asparagus in the spring. Use the vegetables you have to hand. It will always be a treat.

Ingredients

The vegetables

2 lbs cauliflower, florets separated
1 Romanesco broccoli, florets separated (or broccolini)
1 1/2 lbs carrots, peeled and cut into 1/2-inch slices on a bias*
4 leeks, root end trimmed, cleaned, and chopped into 1-inch pieces*
1 butternut or delicata squash, peeled, halved, seeds removed, and sliced
1 red or yellow onion, peeled and cut into eighths*
Olive oil
1 Tbsp za’atar
3 pinches coarse sea salt
8–10 grinds black pepper
2 handfuls small purple kale leaves
2 Tbsps finely chopped chives

The sauce

2/3 cup Greek yogurt
3 Tbsps tahini
1 finely chopped green onion*
1 1/2 Tbsps olive oil
1 1/2 Tbsps lemon juice
Pinch of salt
4 grinds of black pepper

*Keep trimmings for a Simple or Roasted Vegetable Stock

Instructions

Preheat the oven to 400°F.
Place the cauliflower, broccoli, carrots, leeks, squash, and onion in a large roasting pan or on a sheet pan. Drizzle with olive oil. Scatter the za’atar over the top and season with salt and pepper. Toss to combine. Roast for 40 minutes, turning the vegetables over once or twice to ensure they are nicely browned.
Remove the pan from the oven, add the purple kale, toss to combine, and return the pan to the oven to cook for 5 more minutes. Once cooked, scatter the chives over the dish.
While the vegetables are roasting, prepare the yogurt sauce. Place all the sauce ingredients into a small mixing bowl and stir to combine. If the mixture is too thick (it should have a pourable consistency), add 1 tablespoon of hot water at a time to thin it. Keep at room temperature while the vegetables finish cooking. Drizzle the sauce over the vegetables when ready to serve.

This recipe comes from Pascale’s latest cookbook, Flavour—Savouring The Seasons: Recipes From The Market Table. Learn more at pascaleskitchen.com.

RECIPE: Simple or Roasted Vegetable Stock

Fresh stocks are an essential and vibrant foundation for any soup, stew, tagine, or sauce. A stock full of flavor and fresh ingredients will improve any dish, and most stocks are easy and economical to make. Use simple vegetable stock when cooking rice, risotto, and couscous to enhance the grains. Roasted stocks add depth and richness of flavor to all soups and stews — they are truly worth the effort.

Ingredients

1 gallon-size freezer bag full of veggie trimmings
or
2 large onions, peeled and diced
4–5 carrots, peeled and diced
2 leeks, carefully cleaned, trimmed, and quartered lengthwise
1–3 celery stalks, diced
and
2 Tbsps olive oil, if roasting
3 quarts of water
1 bunch parsley stems or 1 bouquet garni (1 bay leaf, 6–8 stems parsley, and 6–8 stems fresh thyme, loosely tied together with kitchen twine)
3 good turns of freshly ground pepper

Instructions

If roasting, preheat the oven to 350°F. In a large roasting pan, add the freezer bag of veggies or the onions, carrots, leeks, and celery. Drizzle with olive oil, toss to coat, and roast for 45 minutes.
For the simple stock or the next step for the roasted stock, fill a 4-quart stockpot three-quarters full with cold water, and add veggies, herbs of choice, and pepper. Bring to a simmer and cook for 30 to 45 minutes.
Carefully strain the stock through a fine mesh sieve into a clean bowl, but do not press down on the solids, as this will make the stock cloudy.

Stock tips

Carrot peels, onion skins, celery leaves, tops of celeriac, parsley stems, and green onion and leek trimmings can be collected and simmered to make a hearty vegetable stock, full of natural flavor. Keep a gallon-size freezer bag in your kitchen to collect the peels and trimmings. Once the bag is full, you can easily make a big batch of homemade stock. Some veggies have a stronger flavor that could be off-putting — or just make sure you use broccoli stem shavings in a stock for broccoli soup!

RECIPE: Romanesco Broccoli and Leek Soup

I like to call the magnificently shaped chartreuse-hued Romanesco the Fibonacci broccoli as it is one of the most stunning representations of the mathematician’s fractal spiral. Each cauliflower-like head is a work of art with a nuttier, slightly sweeter flavor than its namesake. They can be roasted, grilled, or steamed. This recipe pairs them with creamy leeks to make a luscious soup.

Ingredients

Olive oil
3 large leeks, halved lengthwise, cleaned and finely chopped*
1/2 tsp coarse sea salt
10 grinds of black pepper
1 1/2 lbs Romanesco broccoli, florets separated
4 finely chopped green onions*
4 cups vegetable stock
1 Tbsp finely chopped chives*
4 slices grilled sourdough or ciabatta

*Keep trimmings for a Simple or Roasted Vegetable Stock

Instructions

Pour 1 1/2 tablespoons of olive oil into a large saucepan over medium heat. Add the leeks, salt, and pepper, and cook, stirring frequently, until soft and tender, approximately 7 to 8 minutes.
Add the Romanesco florets and green onions to the leeks. Cook for 3 to 4 minutes. If the mixture feels a little dry, add 1/2 tablespoon of olive oil. Pour the vegetable stock into the pan and bring to a simmer, uncovered. Cook until the Romanesco is soft, about 12 to 15 minutes, depending on the size of the florets.
To get a completely smooth texture for the soup, purée it for at least 1 minute at high speed in a blender (remember to hold down the lid) or for at least 3 minutes if you use an immersion blender.
Pour the soup into serving bowls, add a swirl of olive oil and a scattering of chives. Serve with grilled sourdough or ciabatta.