- 1 1/2 pounds turnips, peeled, cut into 1″ pieces
- Kosher salt
- 1/2 cup heavy cream
- 3 teaspoons olive oil, divided
- 2 1/2 pounds rack of lamb (1 or 2 racks), bones frenched
- Freshly ground black pepper
- 5 sprigs thyme, divided
- 1 cup dry Marsala
- 1 garlic clove, peeled
- 2 bunches flat-leaf spinach, trimmed
- Preheat oven to 400°F. Cook turnips in a large saucepan of boiling, salted water until tender, 10-15 minutes. Drain. Return to pan; add cream. Bring to a boil. Reduce heat and simmer until cream coats turnips, about 4 minutes. Purée turnip mixture in a food processor or with an immersion blender until smooth. Cover and keep warm.
- Meanwhile, heat 1 teaspoon oil in a large ovenproof skillet over medium-high heat. Season lamb with salt and pepper. Cook fat side down until brown, 5-8 minutes.
- Turn lamb over. Tuck 4 thyme sprigs under; place in oven. Roast until an instant-read thermometer inserted into center registers 125°F for medium-rare, 15-25 minutes. Let rest on a plate for 10 minutes.
- Drain fat from skillet; add Marsala. Bring to a boil. Reduce heat; simmer, stirring and scraping up browned bits from bottom of skillet, until reduced by half, 5-8 minutes.
- Meanwhile, heat remaining 2 teaspoons oil in a large skillet over medium heat. Add garlic and remaining thyme sprig; stir until beginning to brown, about 1 minute; discard garlic and thyme sprig. Add spinach by the handful, tossing and allowing it to wilt slightly between additions. Season with salt and pepper. Cook until tender, about 4 minutes.
- Cut lamb between bones into chops and serve with spinach, turnip purée, and Marsala sauce.