Preheat the oven to 200°C (390°F) using conventional oven settings (top and bottom heat). Cut the cauliflower into small florets, wash them, and place them in a large casserole dish. Peel the onion and cut it into quarters or eighths, then add it to the cauliflower along with the unpeeled garlic cloves. Wash the potato and cut it into small cubes, approximately one centimeter (½ inch) in size.

Mix the vegetables with olive oil, a little salt and pepper, and cover the casserole dish with aluminum foil. Bake in the oven at 200°C for 40 minutes, then roast uncovered for another 10 minutes.

Grate the bread rolls on a box grater or in a food processor. Zest about half a lemon, press a garlic clove through a garlic press or dice it finely.

In a skillet, lightly sauté the garlic and lemon zest in olive oil for a short time. Add the bread crumbs and cook over medium heat for 3–5 minutes, stirring or shaking the pan frequently, until golden brown. Season with salt, pepper, and herbs to taste.

Drain and thoroughly rinse the beans in a colander. Place the vegetables, beans, vegetable broth, and nutritional yeast in a blender and puree until smooth. Alternatively, you can put all the ingredients in a pot and use an immersion blender to puree them. Season the soup with salt, pepper, and the juice of half a lemon to taste.

Season the soup with salt, pepper, and the juice of half a lemon. Serve with the crispy topping and some fresh bread.