Greek-Style Bread Pudding

Ingredients

• 1 teaspoon olive oil
• 6 cups sliced cremini mushrooms (about 12 ounces)
• 1/2 cup chopped onion
• 1 garlic clove, minced
• 1/2 cup golden raisins
• 1/4 teaspoon black pepper
• 1/8 teaspoon salt
• 1 (14 1/2-ounce) can Italian-style diced tomatoes, drained
• 1 (10-ounce) package frozen chopped spinach, thawed, drained, and squeezed dry
• 2 cups 1% low-fat milk
• 1 cup (4 ounces) crumbled feta cheese, divided
• 4 large eggs
• 8 ounces (1-inch) cubed day-old Italian bread (about 9 cups)
• Cooking spray