Cream of Asparagus of Soup

My mom makes this a lot and I finally tried it.  It is very creamy and delicious.  I know many of you are freaked out by this recipe, but trust me it is good!  My kids like it a lot too.  Great on its own or with some oyster crackers on top...especially good with a grilled cheese sandwich on the side!  -Kristin

2 pounds green asparagus, washed
1 large onion, chopped
3 Tablespoons butter
5-6 cups chicken broth
1/2 cup half and half or heavy cream
1/4 teaspoon lemon juice, opt.

• Cut stalks and all remaining asparagus into 1/2 inch pieces.
• Cook onion in 2 tablespoons butter in pot over low heat, stirring until softened.
• Add asparagus pieces and salt and pepper to taste.  Cook and stir 5 minutes.
• Add broth and simmer, covered, until asparagus is VERY tender. (15-25 minutes)
• Remove from heat and cool a bit.
• Puree soup in small batches until very smooth and return to pot.  (Be careful pureeing this...the steam can cause the top of the blender to pop off.  Work in small batches and press the top of blender down while holding a dish towel.  That seems to work for me!)
• Stir in half and half.
• Bring soup back to simmer and stir in butter.
• Add lemon juice if desired.