- Place the potatoes in a pot and cover with cold water. Season with salt. Bring to a boil and simmer for 25 minutes or until tender. Drain. Return the potatoes to the pot. With a potato masher, crush the potatoes until smooth. Season with salt and pepper. Using a spatula, gently fold the salmon into the potatoes, being careful to keep some larger pieces of salmon intact.
- Meanwhile, in a small pot over medium heat, melt the butter. Add the flour and cook for 1 minute while stirring. Whisk in the milk. Bring to a boil, then simmer gently for 5 minutes while stirring. Add the cheddar and Parmesan. Cook until the cheese has melted. Season with salt and pepper
- In another pot of salted boiling water, cook the broccoli until al dente. Drain.
- Divide the potato mixture among four plates. Cover with the sauce and a sprinkling of parsley, and top with the broccoli.