Halve the potatoes and cook in a big pot of salted water until just fork tender.
Drain and allow to dry in the strainer for a few minutes.
Tip the potatoes into a greased sheet pan then drizzle with olive oil and season generously with salt and pepper.
Place in the oven and allow to roast for 15 minutes until the potatoes start to turn golden brown.
In a small bowl, mix together the softened butter, crushed garlic, a teaspoon chilli flakes, dried oregano, lemon juice and a pinch of salt and pepper.
In a medium bowl, toss the broccolini with a few teaspoons of olive oil, salt and pepper then add to the pan with a few lemon slices.
Remove the potatoes from the oven. Add the salmon to the pan with the potatoes, skin-side down, then spread the butter over the top of each fillet of salmon. Add the broccolini to the pan.
Place back in the oven and allow to cook for 15 minutes until the salmon and broccolini are cooked.
Remove from the oven and serve with extra lemon wedges for squeezing.