01 - Preheat the oven to 400°F (200°C). Line a baking sheet with parchment paper or lightly grease it.
02 - In a small bowl, whisk together Dijon mustard, olive oil, lemon juice, lemon zest, minced garlic, honey, thyme, salt, and black pepper until thoroughly blended.
03 - Place the salmon fillets skin side down, if applicable, on the prepared baking sheet. Pat fillets dry with paper towels.
04 - Brush the lemon Dijon mixture generously over each salmon fillet, ensuring full coating on all sides.
05 - Place a lemon slice on each salmon fillet.
06 - Bake in the preheated oven for 15 to 18 minutes, or until the salmon flakes easily with a fork and reaches an internal temperature of 145°F (63°C).
07 - Garnish with chopped fresh parsley if desired. Serve immediately.