Preheat the oven to 350 degrees. Remove the stems from the mushroom caps. Finely chop the stems and set aside.
Heat the oil in a large skillet over medium high heat. Add the garlic, mushroom stems, spinach, crab meat and seasonings to the skillet and sauté for about 5 minutes or until the spinach is wilted and the garlic and mushroom stems have softened. Remove from the heat and stir in the ricotta cheese, ¼ cup of Parmesan cheese and ½ cup of the panko breadcrumbs. Mix well. Spoon the filling mixture into each of the mushroom caps. Place the remaining panko in a small bowl and then gently dip the tops of the stuffed mushrooms into the panko to give it a nice crunchy topping. Then place on a rimmed baking sheet and bake for 20 minutes or until the mushroom filling is piping hot and the mushrooms have released their liquid onto the tray. Serve and enjoy!
Tip: If your panko hasn’t browned by the end of cooking time, place them under the broiler for a minute or two to brown up the top.