To get an idea of the different flavor, purchase a can of Campbell's split pea soup, and a can of Habitant French-Canadian recipe pea soup. The yellow split peas have a milder, less sweet flavor than do the green split peas. They go very well with a bit of pork, a bit of cream, diced onion, and finally, salt & pepper. That's all you really need. Whole yellow dried peas also make a wonderful soup.
With either kind of split pea soup, simmer the soup until the peas litteraly disintigrate, stirring every half hour or so. Total cooking time should be no less than an hour. There should be no hard grains in the soup. Add shaved or grated carrot, and diced onion half way through the cooking time. When all is done, carefully pour the soup into a blender, or use an immesrsion blender to make it silky smooth. If enough peas were used, the solids will remain in suspension. But I usually make a blonde roux with flour and butter, add soup broth to thin, and mix the thinned roux into the soup. This binds the soup, that is, keeps the solids in suspension. They don't settle to the bottom. The soup comes out much creamier that way.
Both yellow and green split peas are enhanced by a bit of mesquite flavored liquid smoke. But add by drops. Too much will ruin the soup and cause significant heartburn. And I don't know about you, but I don't like heartburn. It's painful.
Seeeeeeeya; Goodweed of the North