Preheat the oven to 375 degrees F. Prepare a baking sheet by spraying it with non-stick cooking spray and greasing it lightly. Set aside.

Turn the stems of the mushrooms counterclockwise to remove them, then place them in a food processor along with sun-dried tomatoes. Pulse until finely chopped (alternatively you can chop by hand). Set aside.

Heat a large skillet over medium-high heat. Crumble the sausage as it cooks with the onion until the sausage is nearly done cooking and remove from heat. Drain the excess grease.

Mix in the tomato and mushroom combination, then add Worcestershire sauce and the rest of the ingredients. Continue to heat for a further three minutes, or until the sausage is well cooked through. Sauté the garlic for thirty seconds after adding it.

Reduce the heat to low, toss in the cream cheese until it has melted, and then stir in the sour cream, mozzarella, and parmesan cheese until they have melted as well.

Turn off the heat and mix in some fresh basil leaves. Set aside.

In a bowl of medium size, melt two tablespoons of butter using the microwave. After adding the panko, toss the mixture until it is uniformly covered. Set aside.

In a separate medium bowl, melt two tablespoons of butter and toss in two teaspoons of lemon juice until combined.

Coat the outside of each mushroom in the lemon butter mixture and set them aside. Place the mushrooms, cavity side up, on the baking sheet that has been prepared.

Put the filling in a bag that is suitable for the freezer, and then cut a corner off of it. Squeeze the filling into the mushrooms until they are completely bursting at the seams.

The mixture should be patted down to make a rounded top, and then the top of each mushroom should be dipped into the panko mixture before the mushrooms are returned to the baking sheet.