1. Preheat the oven to 375F.
2. Make the lemon garlic sauce: Whisk together lemon juice, olive oil, dijon, mustard, dried oregano, pressed garlic cloves and salt and pepper. Set aside.
3. To a large sheet pan add halved baby potatoes Drizzle with half of the lemon garlic sauce, toss and then roast for 20 minutes.
4. Once the potatoes have roasted, add the halved tomatoes to the sheet pan and gently toss. Nestle the salmon filets in between the potatoes and tomatoes on the pan. Divide the rest of the lemon garlic sauce evenly between the filets, drizzling on top of each. Finally, add the lemon slices to the sheet pan, on the salmon filets and nestled into the potatoes and tomatoes.
5. Place back in the oven for 8-12 minutes or until the salmon is cooked through to your desired temperature.
6. Serve topped with cubed/crumbled feta, fresh herbs and tzatziki.