Vegetable Stock

I write often on this blog about the need for good vegetable stock.

I don't buy commercial stock or bouillon cubes because I'm not a fan of some of the ingredients. Plus it's so easy to whip up a batch of a superior stock at home in the slow cooker.

The secret to this stock is roasting the vegetables in a little olive oil before adding them to the pot. Just as it does with meat bones when making a meat broth, the roasting heightens the flavors and adds a caramelized taste that enhances the broth.

Parsnips are the other secret ingredient. Leave them out if you can't find them and the stock will still be good. But if you have one (and they last in the fridge for months, so if you find some make sure to buy a large bunch), add it and taste the difference.

I find this stock is so rich and good that I use only a quarter of what a recipe calls for, replacing the rest of the liquid with plain water. So the 7-8 cups this recipe makes actually extends to 3 or 4 times that much. I freeze it in 1 and 1 1/2 cup containers, ready to be added to soups and stews as the secret ingredient that makes all the difference.

You could make this same recipe on the stove instead of in a slow cooker. It would cook in a couple of hours. Make sure not to let too much water boil off - keep it at a slow simmer.

But honestly, even if this is the only recipe you use a slow cooker for, it's worth the investment.

Vegetable Stock
1 large onion, peeled and sliced 1/2 inch thick
2 large carrots, scrubbed and cut in 1 inch pieces
2 medium red potatoes, scrubbed and cut in 1 inch pieces
1 large parsnip, peeled and cut in 1 inch pieces
1 stalk celery, cut in 1 inch pieces
1 tbsp olive oil
3 cloves garlic
salt and pepper
4 dried shiitake or porcini mushrooms
2 bay leaves
1/2 tsp black peppercorns
1 tbsp tamari (or other soy sauce)

Toss the onion, carrots, potatoes, parsnip and celery in the olive oil. Crush the unpeeled garlic cloves with the side of a knife and add them too. Toss with salt and pepper, spread out in a roasting pan, and bake at 450°F for 30 minutes, stirring halfway through. The onions might get a little blackened - that's okay, it adds to the flavor.

Meanwhile, soak the dried mushrooms in 1 cup hot water until softened. Slice the mushrooms and put in the slow cooker. Strain the water to remove any grit - I use a paper coffee filter - and add the water to the slow cooker too.

When the vegetables are done, add them to the slow cooker along with the bay leaves, peppercorns and tamari. Pour in 7 cups water, turn the slow cooker to low, put the lid on, and leave it for 8 hours. Resist the urge to lift the lid and give it a stir. Also, you might want to leave the house. Slow cookers are safe - they use the same amount of energy as a light bulb - and the aroma of this stock cooking will make you very hungry.

Strain the vegetables from the stock and discard them on the compost heap. You can taste one if you like - all the flavor will have gone into the stock.

Use the stock right away in soup or a stew, refrigerate for a few days, or freeze in containers for later use. In theory it can last a year in the freezer, but you'll find you use it up long before then.

Fortunately it's easy to cook up another batch.