Chop the broccoli florets and add to a medium bowl and reserve for later.
Peel the outer layer of the stem, then dice the peeled stem.
Add butter to a large dutch oven on medium high heat.
Add broccoli stem, onion and potato and stir well.
Cook for 6-8 minutes, until onions are translucent.
Add flour and whisk well until flour is no longer visible.
Add in broth, whisking while adding, and bring to a boil.
Reduce heat to a simmer and cook for 15 minutes.
Add salt, pepper, nutmeg, evaporated milk, Worcestershire sauce and reserved broccoli florets and stir well until creamy.
Cook for 5 minutes until soup is slightly thickened.
Add in cheddar cheese, stir until melted and creamy, then serve.