• Heat broiler to high. Wash and dry produce. • Dice potatoes into ½-inch pieces (peel first if desired). Strip thyme leaves from stems; roughly chop leaves. Trim, peel, and halve carrot lengthwise; slice crosswise into ¼-inch-thick half-moons. Finely dice celery. Halve, peel, and finely chop onion. Peel and mince garlic.

• Place potatoes in a medium pot with enough salted water to cover by 2 inches. Bring to a boil and cook until tender, 15-20 minutes. • Drain and return potatoes to pot. Mash with sour cream, 1 TBSP butter (2 TBSP for 4 servings), and 1 tsp chopped thyme until smooth and creamy, adding splashes of water as needed. Season generously with salt and pepper. • Cover to keep warm.

• Meanwhile, heat a drizzle of oil in a medium, preferably ovenproof, pan (use a large pan for 4 servings) over medium-high heat. Add carrot; season with salt and pepper. Cook, stirring, until slightly softened, 2-3 minutes. • Add celery, onion, and a large drizzle of oil; season with salt and pepper. Cook, stirring, until veggies are just tender, 5-7 minutes. TIP: If veggies begin to brown too quickly, add a splash of water. • Stir in garlic and 2 tsp chopped thyme; cook until fragrant, 30 seconds.

• Remove sausage* from casing; discard casing. • Add sausage to pan with veggies. Cook, breaking up meat into pieces, until browned and cooked through, 4-6 minutes. • Add flour; cook, stirring, until thoroughly combined, 1 minute.

• Add ¾ cup crushed tomatoes (1 cup for 4 servings) to pan with sausage mixture. (Be sure to measure crushed tomatoes.) Stir in stock concentrate and bring to a boil. Cook until mixture is very thick, 1-2 minutes. • Turn off heat. Taste and season with salt and pepper. TIP: If your pan isn’t ovenproof, transfer filling to a baking dish now.

• Top sausage filling with an even layer of mashed potatoes, leaving a 1-inch border around edge of pan. Evenly sprinkle mashed potatoes with cheddar. Broil until browned, 3-4 minutes. TIP: Watch carefully to avoid burning. • Let cool at least 5 minutes, then divide between plates and serve.