Melt the butter in a frying pan. Add the salmon skin-side down, season with salt and freshly ground black pepper and squeeze over a little lemon juice. Fry for 2-3 minutes, then turn the salmon over and fry for a further 1-2 minutes, or until cooked through. Squeeze over a little more lemon juice and taste to check the seasoning. Remove from the pan and set aside.
Place the broccoli into a pan of boiling salted water and boil for 3-4 minutes, or until al dente. Drain the broccoli.
To serve, pile the broccoli onto a serving plate and top with the pan-fried salmon. Garnish with lemon wedges.