Jenny Rosenstrach is a food writer and New York Times bestselling cookbook author. She has written the popular Dinner: A Love Story blog for over a decade. She shared this recipe from her newest cookbook, The Weekday Vegetarians Get Simple.

Copyright © 2024 by Jenny Rosenstrach. Photographs copyright © 2024 by Christine Han. Published by Clarkson Potter, an imprint of Crown Publishing Group.

• 2 tablespoons unsalted butter 
• 1 tablespoon extra-virgin olive oil, plus more for drizzling
• 1 large yellow onion, thinly sliced
• Kosher salt and freshly ground black pepper to taste
• 1 garlic clove, minced
• ¼ teaspoon red pepper flakes
• 1 tablespoon tomato paste
• 2 (15-ounce) cans white beans, such as cannellini, drained and rinsed
• 4 cups vegetable broth, homemade or Better Than Bouillon
• 1 (14.5-ounce) can diced tomatoes, undrained
• 1 (12-ounce) bag shredded slaw vegetables (or 5 cups of your own shredded vegetables such as cabbage, broccoli, carrots, cauliflower, etc.)
• 1 tablespoon sherry vinegar, plus more to taste Handful of fresh basil leaves, torn, for serving Freshly grated or shaved Parmesan cheese, for serving

Serves 4

1. In a medium pot, melt the butter with the olive oil over medium-high heat. Add the onion and season with salt and pepper. Cook until they’re nicely browned and frizzled (don’t stir too much), 8 to 10 minutes. Using a slotted spoon, transfer one-quarter of the onions to a small bowl and set aside (you’ll use this as a topping). Add the garlic and red pepper flakes to the remaining onion in the pot and cook until golden and aromatic, about another minute. Add the tomato paste and cook another minute, until it deepens in color and looks toasty.
2. Reduce the heat to medium, add the beans, and season with salt and pepper. Using a fork or potato masher, smash roughly half of the beans in the pot, breaking them up to release their starch (this is what will thicken the soup). Add the broth and tomatoes and bring to a boil. Reduce to a simmer and cook until the texture has thickened, about 15 minutes.
3. Stir in the shredded vegetables and the vinegar. Simmer until the vegetables have wilted, 10 to 15 minutes. Taste and season with salt, pepper, and more vinegar if you like.
4. Remove from the heat and stir in the basil. Serve in bowls topped with the reserved frizzled onions, a hefty drizzle of olive oil, some Parm, and freshly ground black pepper.