Mix the butter with the rosemary, 1 tsp olive oil and salt to taste. Combine well and place in the fridge for serving later.
Pre-heat the oven to 200 degrees. Place all the vegetables on a non-stick baking tray and drizzle over olive oil and sea salt. Mix well to coat the vegetables.
Place in the oven for approx 40 mins or until the potatoes are cooked and the peppers starting to 'char'.
Approx 10 minutes before serving, heat a hot plate or grill and cook the lamb steaks to your liking. Once cooked place onto warmed plates and immediately places the butter on top to melt over the lamb. Serve with the tray baked vegetables.