In a large saucepan, combine the first nine ingredients; bring to a boil. Reduce heat; cover and simmer for 1 hour or until peas are tender, stirring occasionally.
Add salt and pepper; simmer 10 minutes longer. Cool slightly. In small batches, puree soup in a blender; return to the pan. Heat for 5 minutes. Garnish with shredded carrots and green onions.