In a medium to large pot, melt the butter and cook the chopped onion until golden.
Add the chicken broth and bring to simmer over medium heat.
Add the broccoli chopped in small stems, salt and pepper to taste, a tablespoon of curry powder, and bring again to simmer.
Simmer for about 15-20 minutes or until the broccoli is tender. Actual time depends on how large the broccoli pieces are.
Pull the pot aside on the stove and either use an immersion blender or transfer the liquid into a food processor. Blend well.
Return the blended liquid into the pot, add the cream and grated cheddar, a bit at a time so it will not clump. Mix well and serve hot, garnished with fresh parsley leaves if you wish. Decorate with a sprinkle of curry powder and a little cream.