Prepare the garlic-herb butter by combining all ingredients in a medium-sized bowl. Stir until the garlic, herbs, and salt are evenly distributed throughout the softened butter.
Transfer the butter mixture to the center of a sheet of plastic wrap and form into a log. Wrap tightly and place inside the refrigerator for 15-20 minutes to become firm.
Heat olive oil in a large skillet over medium-high heat. Pat cod fillets dry with a paper towel and season both sides with salt and black pepper, to taste.
Add filets to hot skillet and cook for 2-3 minutes, or until they become golden brown. Reduce heat to medium and carefully flip each fillet. Top each fillet with an equal amount of herb butter and continue cooking for another 3-4 minutes. While cooking, spoon the herb butter back over the filets as it melts.
Remove from heat and transfer fillets to individual serving plates. Drizzle with melted herb butter and garnish with some fresh chopped parsley, if desired.
Serve immediately with some oven-roasted asparagus tossed with remaining herb butter from the skillet or your choice of sides. Enjoy!