Stuffed Portobello Mushrooms

Bahan-bahan (4 porsi)

• 4 portobello mushrooms
• 2 tablespoons olive oil
• ½ yellow onion (finely diced)
• 2 cloves garlic (minced)
• ¼ cup finely diced red bell pepper
• 4 ounces cream cheese (softened)
• ¼ cup sour cream
• 2 cups cooked chopped chicken (or 14 oz diced artichokes)
• 5 ounces frozen chopped spinach (thawed and squeezed dry)
• 1 cup shredded mozzarella cheese (divided)
• ½ cup shredded Parmesan cheese
• ½ teaspoon black pepper (or to taste)
• ¼ teaspoon salt (or to taste)