First, take a large pot, and then add 4 tablespoons of Extra Virgin Olive Oil from Spain. Place over medium heat and add the onion, carrots, celery and garlic, and saut for about 4 minutes.
Add 2 cups of stock, the potatoes and some salt. Turn up the heat until it boils and then add the broccoli. Cover the pot, turn down the heat and let it simmer for 15 minutes.
If necessary, add another cup of stock and let it cook for another 5 minutes. All the vegetables should be tender. Then remove from the heat.
Put the other 2 tablespoons of Extra Virgin Olive Oil from Spain in a pan, put it on the burner (keeping it at the same temperature as before), and add the whole wheat flour. Cook, stirring continuously with a whisk, and adding the milk, little by little. Remember that the mixture should be thick and free of lumps. Add salt and pepper, and then stir.
Add this sauce to the vegetable soup and let it cook for a few more minutes.
Remove the chowder from the heat and check the salt. If you want to make it a bit lighter, you can add more stock.
Serve on a plate and garnish with cheese to taste.
