Joe's Special Beef Fritatta

Ingredients (11)

• 2 tablespoons olive oil
• 2 pounds lean ground beef
• 2 medium onions (finely chopped)
• 2 garlic cloves (finely minced)
• Optional: 1/2 pound mushrooms (sliced)
• 1 1/4 teaspoons salt
• 1/4 teaspoon ground nutmeg
• 1/4 teaspoon dry oregano
• 1/4 teaspoon pepper
• 1 (10-ounce) package frozen chopped spinach (thawed and squeezed dry; or 1/2 pound fresh spinach, rinsed, stems removed and leaves chopped)
• 4 to 6 large eggs (lightly beaten)