Rinse mushrooms and pat dry. Marinate mushrooms for 15 minutes in equal parts red wine vinegar, balsamic vinegar and Worcestershire sauce.
Brown ½ pound of ground meat, adding a dash of garlic salt. Place browned meat in a mixing bowl and set aside.
Sauté onion, bell pepper, garlic, spinach, basil. After sautéing, mix with the meat. Add goat cheese and a pinch of cayenne, smoked paprika, and fresh ground pepper.
Place meat mixture in mushrooms and bake for 15 minutes. Remove from oven and let sit for a few minutes before serving.