Preheat 350 F, option to line a baking sheet with parchment paper for easy cleanup.
Carefully remove the mushroom stems. Slice the ends off, then dice the rest into small pieces. Place mushroom caps on a rimmed baking sheet.
Heat oil in a large pan over medium heat. Once shimmering, add the garlic and chopped mushroom stems. Saute until soft, about 5 minutes. Place in a large bowl.
To the bowl, add the cream cheese, parmesan cheese, parsley, pepper, and smoked paprika. Stir until well combined. Fill each of the caps with a generous amount of the filling. (you may have some leftovers--save it for toast!)
Bake in the preheated oven for 20 minutes, you'll know they're done once the filling is heated through and the mushrooms are soft. Enjoy!