1. Preheat oven to 375 degrees.

2. Wash and dry mushrooms. Pull off the stems and separate. Chop all stems finely set aside.

3. Heat olive oil and butter in skillet over medium high heat. Add chopped onion and mushroom stems. Saute for several minutes until starting to golden. Add panko, salt and pepper. Stir and continue cooking for 2 minutes.

4. Remove from heat and set aside. Squeeze excess liquid out of spinach and set aside.

5. In large bowl combine cream cheese, sour cream and grated cheeses. Then add cooled mushroom panko mixture. Fold to combine. Add spinach, salt, pepper and artichoke hearts. Add hot sauce if desired. Fold to combine.

6. Using a spoon (or if you're fearless, like me, use your hands) mount the mixture into the mushroom caps. Use a spoon (again, or your hands) to round the top of the mushroom. Place on foil on baking sheet and bake for 20-25 minutes (this is for normal sized mushrooms - if you packed your mushrooms until you could barely tell they were mushrooms anymore I'd say give it a solid 33 minutes).

Serve and enjoy all that is mushroomy goodness.

Photo c/o ThePioneerWoman.com