Celery Root Shepherd's Pie

Ingredients

• 8 servings stew meat 
• 8 servings beets mashed
• 0.3 teaspoon pepper black
• 2 tablespoons butter 
• 2 large carrots peeled finely chopped
• 2 lbs celery root peeled cut into 2-inch pieces
• 1 teaspoon thyme sprigs fresh finely chopped
• 1 clove garlic minced
• 1 pound ground beef 
• 0.8 cup yogurt plain low-fat
• 0.3 cup milk 2%
• 8 ounces mushrooms mixed cleaned sliced
• 1 pinch nutmeg 
• 2 tablespoons olive oil extra virgin extra-virgin
• 1  onion thinly sliced
• 0.5 cup parmesan 
• 1 sprig rosemary 
• 2 lbs baking potatoes peeled cut into 2-inch pieces
• 1 teaspoon water plus more for salting the water
• 0.3 cup tomato paste 

Equipment

• bowl
• frying pan
• oven
• pot
• casserole dish

Directions

1. Place cut potatoes and celery root in large pot; add cold water till covered. Bring to boil, salt generously, cover and simmer until potatoes are easily pierced with fork (10-12 minutes).
2. Drain well; return to pot off the heat to dry.
3. Heat 1 TBSP oil in large skillet over medium-high heat.
4. Add onion, garlic, mushrooms, and thyme; cook, stirring occasionally, until mushrooms are golden and soft (about 8 minutes).
5. Remove and spread along bottom of a 2-quart casserole dish.
6. Heat 1 TBSP oil in the same skillet; add the beef or lamb, carrot, rosemary, and nutmeg; cook until beef is brown and carrot is tender (about 8 minutes). Stir in tomato paste.
7. Layer over mushroom-onion mixture.
8. Finish the mashed veggies: Pass potatoes and celery root through a food mill into a bowl, adding butter as you go. Stir in yogurt and milk for a pure. Season with salt and pepper.
9. Swirl mashed potatoes and celery root over stew with back of a spoon; sprinkle on cheese.
10. Bake until cooked through and cheese is golden brown (15 minutes).
11. Serve warm.