Preheat the oven to 425 degrees F.
Coat the squash halves with 1 tsp olive oil.
Season the inside with salt and pepper and place cut-side down on a baking sheet lined with parchment paper.
Bake until very tender, about 40-45 minutes.
Set aside to cool.
In a large saucepan over med-high heat, add the remaining oil and add the onions until caramelized, about 6 mins.
Add the crumbled sausage and cook until meat is golden brown.
Add the garlic, sage, and marjoram, and cook for 1 minute
Add the cooled squash and chicken broth, stir well and bring to a boil.
Reduce heat to low and simmer for 30 minutes, stirring occasionally.
Using either a hand-help immersion blender or in batches in a food processor or blender, puree the soup.
When a smooth texture is accomplished, add lemon juice and adjust seasoning to taste.
Stir and serve.