In the sautee setting, sautee the shallot and garlic with the butter in the instant pot. Add the chicken stock (or white wine) and stir.
Turn off the saute setting and add the the mussels. Select Manual mode for 5 minutes. And Natural release.
Easy Mussels Recipe https://www.mynourishedhome.com/easy-mussels-recipe/ April 20, 2019