The Portfolio diet combines four foods, all of which individually lowered cholesterol in earlier studies. The diet was designed by University of Toronto reseachers, and published in Metabolism and JAMA in 2003. The four foods that make up the Portfolio diet are:

Soluble fiber may come from fruits, vegetables, legumes and oat bran. The following data is from the Portfolio paper and a paper they reference by James W Anderson, Dietary fiber content of selected foods, published in the American Journal of Clinical Nutrition, 1988: 440-7.

Eggplant (200 grams every other day) and Okra (100 grams every other day) were additional sources of souble fiber used in the Portfolio study.
Soy protein may be a bit harder to incorporate into your diet, but can be done gradually with the following foods:

Plant sterols at the levels required by the Portfolio diet can only be acheived by using margarine like products such as Benecol© or Take Control©. The only food which has more than 100 mg of plant sterols per serving is an Avacado (130 mg per 6 ounces). Corn Oil is another source with 130 mg per tablespoon. Soybeans can not only be a source of soy protein, but they also have 45 mg of plant sterols per 4 ounces.

Additional Portfolio information may be found at the Almond Board of California's Portfolio Site.