1. Sauté the broccoli in a soup pot. As it begins to lightly brown, add the onions and reduce the heat.
2. Continue to lightly sauté until onions are translucent and then add the garlic.
3. Sauté until garlic is fragrant, 1 minute or so.
4. Add the vegetable stock.
5. Simmer lightly until the broccoli is easily pierced.
6. Remove from the heat and allow to cool.
7. Once cooled, blend with an immersion blender.
8. Stir in the cayenne and cream.
9. Taste and adjust seasoning with the kosher salt.
10. If needed, thicken with the beurre manie.

Beurre Manie

1. Knead together the equal part of butter and flour.
2. Once combined, drop the mixture into the soup by chunks, whisking after each addition until the soup is thickened to your liking.