1. Preheat the oven to 400°F.
2. Pat the cod fillets dry with a paper towel, and then place them in an oven-safe baking dish.
3. In a small bowl, mix together the butter, olive oil, garlic, herbs, salt, and pepper.
4. Spread the herbed butter onto the fillets, evenly.
5. Then, lay the lemon slices on, around, and slightly under the buttered cod.
6. Then, place the cod in the oven and let bake for 13 to 15 minutes, until it's flaky.
7. After that time, remove the cod from the oven, serve, and enjoy!