Nothing beats homemade soup, and this is a perennial favorite on cold winter days. The soup is thickened with a small potato, while a bit of cream adds a rich, mellow note. If you don't include dairy in your diet, leave it out; the soup will still be delicious.
Combine the broccoli, potato, leeks, and chicken stock in a large pot and bring to a simmer over medium-high heat. Cover the pan, reduce the heat to maintain a simmer, and cook until the vegetables are tender, 20 to 25 minutes.
Transfer the mixture to a food processor and purée; it may be necessary to do this in batches. Return the purée to the pot and add the cream. Reheat gently and season to taste with salt and pepper. Serve hot.