Melt butter in a large Dutch oven over low heat. Add onions and next 2 ingredients, and cook, stirring often, 30 to 35 minutes or until onions are caramel colored. (Adjust heat to prevent scorching.) Add apples, and cook, stirring often, 5 minutes. Add broth and next 2 ingredients. Increase heat to medium, and bring to a boil, stirring occasionally. Reduce heat to medium-low, and simmer, stirring occasionally, 20 to 25 minutes or until apples and potato are tender. Remove from heat, and let stand 15 minutes. Discard bay leaf.
Process mixture with a handheld blender until smooth. Add cream and lemon juice. Return to low heat; simmer, stirring often, 15 minutes. Add salt and pepper. Serve with Cheese Puff Pastries.
Note: We tested with Swanson Certified Organic Chicken Broth.
I made this for guests--fortunately I made it ahead of time because it was so blah I had to add a few things to pep up the flavor--apple cider vinegar and a few splashes of hot sauce. The next day I cooked down more onions with a few stems of thyme and added. I served it although it wasn't up to my usual standards.
My husband and I really liked the flavor of this soup, but it was a bit too thin for our taste. When I make it again - and I will! - I will probably put a half a block of cream cheese into the blender when I puree the soup, and omit the cream.
Because puff pastry can't be rerolled, I just cut mine into 9 squares instead of rounds.