Step 1: Preheat your oven to 425°F (220°C).
Step 2: In a large mixing bowl, combine the melted butter, olive oil, dried oregano, smoked paprika, minced garlic, lemon juice, salt, and pepper. Whisk until well combined.
Step 3: Add the chicken legs to the marinade. Coat thoroughly.
Step 4: Arrange the chicken legs skin-side up in a roasting pan. Scatter lemon slices around for added flavor.
Step 5: Roast in the preheated oven for about 40-45 minutes or until the skin is golden and juices run clear.
Step 6: Let the chicken rest for a few minutes, then garnish with fresh thyme and serve.