In heavy-bottom saucepan, heat butter and oil on medium-low heat. Add onions and cook 10 minutes or until translucent, stirring occasionally.

Add butternut squash, stock, pumpkin, 2 teaspoons salt and 1/2 teaspoon pepper. Heat to Boiling on medium-high heat. Cover and simmer on medium-low heat for 20 minutes or until squash is very tender, stirring occasionally. Process mixture with hand blender until smooth.

Add half-and-half to soup. Heat slowly. Serve with garnishes, if using