In a small bowl, stir together the harissa, honey and lemon juice.
Heat the oil in a large heavy-bottom pan over medium heat. Season the salmon filets on both sides with salt and pepper.
Add the salmon to the pan and cook until golden brown on the bottom, about 3-4 minutes. Flip the salmon and pour in the harissa-honey sauce. Cook, spooning the sauce over the salmon, until the salmon is glazed and reaches your desired temperature (about 2 more minutes to reach 125° for medium-rare).
Transfer the salmon to a large plate, spooning any remaining sauce out of the pan and over the salmon. Serve with rice and parsley, if desired.
This salmon is best enjoyed fresh, but leftovers will keep in the fridge up to 3 days. To reheat, simply cook in a skillet over low heat until warmed through. You can also reheat in the oven or air fryer at 200°F until warm.