1 Tablespoon (Plus A Little Extra To Sprinkle Before Baking)
Freshly ground black pepper
Crushed red chili flakes
Preheat oven to 350°.
Toast pine nuts in small skillet over medium heat until just golden, about 5 to 7 minutes. Watch very closely as pine nuts burn quickly. Set aside.
While pine nuts are toasting, clean mushrooms with a damp cloth. Remove stems, mince stems and set aside. Don’t forget about the pine nuts!
Heat oil over medium heat in large skillet. Add garlic and cook until fragrant, about 1 minute. Be careful not to burn garlic.
Add mushroom stems and sauté until soft, about 5 minutes.
Add tomato. Stir and cook 2 minutes.
Add spinach, basil, pine nuts, 1 tablespoon Parmesan cheese, salt, pepper and crushed red chili flakes. Using tongs, toss all ingredients in skillet, lower heat and cook 2 more minutes.
Remove from heat and slightly cool.
Spoon spinach mixture into mushroom caps. Sprinkle a little Parmesan cheese over prepared mushrooms.
Bake 15 to 20 minutes until mushrooms are cooked.