Soak the porcini mushrooms with enough hot water to cover for 20 minutes. Remove the mushrooms and sieve them through cold running water. Strain the soaking liquid through cheesecloth or paper towel. I use paper coffee filters.
Strip the leaves of the swiss chard from the stalks. Reserve the stalks for another use. Put 1/2 inch water in the bottom of a pan. Add the swiss chard leaves and a little salt. Cook on high until chard is is tend. Drain and chop coarsely.
Place the olive oil, butter and onion in a soup pot. Cook over low heat until the onion is tender and golden, about 10 -12 minutes. Add garlic during the last 2 minutes of cooking.
Add the mushrooms and saute for a few minutes. Add the chard, stir well, and let cook for 2 to 3 minutes. Add the chick peas and let them absorb the flavors for a few minutes. Add the tomatoes and raise the heat to high. Add the broth and the porcini soaking liquid. Bring to a boil, then simmer the soup for 40 minutes with the lid partly on.
Before serving, grind black pepper over the top and stir. Serve with garted Parmesean cheese.