Caramelized Onion-and-Gorgonzola Mashed Potatoes

INGREDIENTS

• 3 pounds Yukon gold potatoes, peeled and quartered
• 1 3/4 teaspoons salt, divided
• 2 tablespoons butter or margarine
• 1 tablespoon olive oil
• 2 medium onions, diced
• 4 garlic cloves, minced
• 2 teaspoons chopped fresh or 1/2 teaspoon dried rosemary
• 1/2 cup butter or margarine
• 3/4 cup half-and-half
• 3/4 cup crumbled Gorgonzola or blue cheese
• 3/4 teaspoon pepper
• Garnish: fresh rosemary sprigs