Homemade Vegetable Broth

Coarsely grate carrots, celeriac, and parsley root. Quarter the leek lengthwise and cut into pieces about 0.5 cm thick. Finely dice onions, mushrooms, and tomatoes. Coarsely chop the flat-leaf parsley.

Heat the oil in a large pot over medium-high heat. Add the grated carrots, celeriac, and parsley root and sauté for about 2 minutes, stirring frequently.

Reduce heat to medium. Add leeks, onions, mushrooms, and tomatoes and sauté for another 8 minutes, stirring occasionally, until the vegetables soften and release their aroma.