A Very Veggie Pesach Bonus Recipe: Broccoli-Potato-Cheese Soup

This is more or less a recipe I got in a brochure that the milk marketing board was handing out at a baseball game.  I made it once before with the adjustments I suggest here, and it was very tasty.  It stays in the refrigerator well enough for a week or so, but definitely doesn't freeze and reheat well.  I've cut the original recipe in half, because the original recipe makes 12 servings.  Obviously, the objective was to sell plenty of milk and cheese.

The only Passover adjustment I made in this recipe is substituting potato starch for flour to make the roux (a mixture of flour and butter that thickens a sauce).  This substitution works very nicely, and should work in any recipe that calls for a roux, such as a cheese sauce or a souffle.  I thought about including a souffle recipe in this series, but I've never had much success making a souffle rise properly, so I didn't feel qualified to explain it.  You're welcome to try it.  Let us know how it goes!

Ingredients:

1. 4 tbsp. butter
2. 1/2 cup onion, chopped
3. 1/4 cup potato starch (or less)
4. 2 cups vegetable broth or water
5. 2 cups milk
6. 1 cup broccoli, chopped
7. 1 cup potatoes, diced
8. 3/4 cup shredded cheddar cheese
9. salt and pepper to taste (optional)

Kashrut Notes:

1. Milk does not require Passover certification if it is purchased before the holiday begins.  Stock up now!
2. Onions, potatoes and broccoli are all fresh produce, which is not a Passover problem according to the Star-K website.
3. Butter: Breakstone's salted and unsalted whipped butter are now in stores marked Kosher for Passover.  See pictures at: http://bit.ly/buk4Ly
4. Manischewitz makes a kosher-for-Passover potato starch that is available in better Passover aisles.  It is also available on Amazon.com, but only in packs of four.
5. Cabot Cheese makes its wonderful sharp cheddar in a Passover run certified by the OU.  You can order it from their website.  UPDATE: Cabot has discontinued its Passover run of cheese! Heartbreaking! There are other sources of Passover cheddar; I recommend Les Petites Fermieres if you can find it; I find it at Wegmans. Make sure it's certified for Passover; it isn't always. 
6. Iodized salt is not kosher for Passover! Star-K's Passover Guide says that non-iodized salts that do not contain dextrose or polysorbates may be used, but ideally you should try to find salt with Passover certification or just skip the salt.
7. Spices are not kosher for Passover without certification, and certified spices are hard to find.  You can skip the pepper if you can't find certified black pepper in your Passover section.
8. I doubt you'll find prepared broth in the average Passover aisle, but you may find Passover-certified Telma soup cubes (vegetable, mushroom, or onion) or Goodman's onion soup mix.  Any of these will do, or you can just use water.

Preparation:

1. Melt butter in a large saucepan (3 quarts)
2. Add onion and cook until transparent
3. Add potato starch gradually, mixing until blended, until the potato starch can't absorb any more butter.  You will likely find that this occurs before you reach the full 1/4 cup -- that quantity was intended for flour, and potato starch thickens somewhat better than flour.  This mixture of fat and starch is called a roux (pronounced: roo), and is the thickening agent in many recipes (onion is not usually a part of it).
4. Stir in broth or water gradually, allowing the roux to absorb the liquid.  Don't let the roux clump in the liquid.
5. Stir in the milk gradually.  Like the broth, allow the roux to spread through the liquid without clumping.
6. Add broccoli and potatoes and cook on low heat for about 30 minutes.
7. Add cheese and salt and pepper and continue stirring over low heat until the cheese melts.

Serve topped with a little extra shredded cheddar.