Peel broccoli stems and chop stems and florets into small pieces. Chop parsley, reserving 2 Tbsp to mince as a garnish.
Place broccoli into vegetable stock and bring to a boil. Reduce heat and simmer until tender (about 5 minutes).
Peel and crush garlic cloves and dice onion. Sauté on medium heat in 1 tsp olive oil for 10 minutes. Add to pot.
Place broccoli, liquid, parsley, thyme, rosemary, and salt in blender and puree until smooth. Set aside.
T make White Sauce: Heat the olive oil in the soup pan. Add flour and cook on low for 10 minutes. Stir in soy milk; bring to a boil while stirring constantly with a whisk, until the sauce thickens (approx 10 minutes). Stir constantly to avoid lumpiness of sauce. If lumps appear, put it through a sieve. Stir in broccoli puree. Add salt and pepper to taste.
Heat gently (don't boil). Serve immediately, garnished with minced parsley