Creamy Peanut Butter Soup

Vegetable cooking spray
1/2 cup chopped onions
1/2 cup chopped carrot
1/2 cup chopped celery
1 leek, cleaned and sliced
2 cloves garlic, minced
3 cups vegetable stock
1 (15 ounce) can Great Northern beans, rinsed and drained
1/2 cup reduced-fat peanut butter
1/2 cup fat-free half-and-half or skim milk
1/2 teaspoon curry powder
2 to 3 teaspoons lemon juice
1 to 2 dashes red pepper sauce
Salt, cayenne and black pepper, to taste
Green onions, thinly sliced, as garnish

Spray large saucepan with cooking spray; heat over medium heat until hot. Saut