White Wine Garlic Butter Sauce Mussels

Rinse the mussels under cold running water. Remove the beards and scrub away any dirt with a small brush. Discard mussels with broken shells and any open ones that don't close when checked.
Heat the olive oil in a large pot and melt the butter in it.
Add the finely chopped onion and cook for 5–6 minutes, until softened without browning. Add the garlic and cook for another 20 seconds.
Pour in the white wine and lemon juice and simmer for 2–3 minutes.
Stir in the dry seasonings, then add ⅓ of the lovage, half of the mussels, and the remaining mussels and lovage on top.
Cover the pot with a glass lid, turn the heat to high, and cook for about 5–6 minutes, until the mussels open. Keep the lid closed and don't shake the pot.
Remove the mussels from the pot and discard any that remain unopened.
Divide the mussels into portions. Stir the sauce to distribute the liquid and aromatics, then spoon it over the mussels without straining. Sprinkle with chopped parsley, if desired, and serve with toast.