Turnip AuGratin

6 servings Prep: 15 m Cook: 45 m Total: 1 h Beginner
5.0/5 (1)
Turnip AuGratin
A Southern comfort classic, this turnip au gratin transforms humble turnips into a creamy, cheesy side dish. Tender turnips are baked in a rich cheddar sauce with a golden breadcrumb topping—perfect alongside roasted meats or as a holiday vegetable dish.

Ingredients

6 servings
  • 3 lbs turnips (approximately 9 medium)
  • 1 tsp salt
  • 1 tsp sugar
  • 2 tbsp butter
  • 1 1/2 cups milk
  • 1 tsp salt or Tony Chachere's or other Cajun Seasonings or Season All
  • Black pepper to taste
  • 2 tbsp flour
  • 3/4 cup shredded Cheddar cheese
  • 1/2 cup breadcrumbs

Step-by-Step Instructions

  1. Preheat oven to 350°F. Peel turnips and cut into 1-inch cubes.
  2. In a medium pot, boil the cut up turnips with 1 tsp salt and sugar in enough water to cover the turnips. Boil until fork-tender, about 10-12 minutes. Drain and set aside.
  3. In a medium saucepan over medium heat, melt the butter. Add the flour and whisk to combine, cooking for 1 minute. Gradually add the milk, whisking constantly to prevent lumps. Stir in 1 tsp salt (or Cajun seasoning), black pepper, cheddar cheese, and 1/4 cup of the breadcrumbs. Cook until the cheese melts and the sauce thickens slightly, about 3-4 minutes.
  4. Gently fold the cooked turnips into the cheese sauce until well coated.
  5. Spray a generous amount of cooking spray to coat an 8x8 casserole dish. Spoon the turnip mixture into the casserole dish, leaving about 1/2 inch from the top as it will bubble during baking. Sprinkle the remaining 1/4 cup breadcrumbs evenly over the top, then top with additional shredded cheese if desired.
  6. Bake at 350°F for 25-30 minutes until the top is golden brown and the casserole is bubbly.

Common Problems and Solutions

Q: Why is my sauce lumpy?

A: Whisk the flour into the melted butter first to make a roux, then add the milk gradually while whisking constantly. This prevents flour clumps from forming in the sauce.

Q: Can I prepare this ahead of time?

A: Yes! Assemble the casserole up to 24 hours ahead, cover tightly, and refrigerate. Let it sit at room temperature for 20-30 minutes before baking, and you may need to add 5-10 minutes to the baking time if it's still cold.

Tips and Techniques

Don’t skip the sugar when boiling the turnips—it helps cut any bitterness and brings out the natural sweetness. For extra flavor, use a sharp cheddar cheese instead of mild.

Ingredient Substitutions

  • turnips: rutabagas
  • cheddar cheese: Gruyere, Swiss, or pepper jack cheese
  • breadcrumbs: crushed Ritz crackers or panko breadcrumbs

Equipment Needed

  • Medium pot for boiling turnips
  • Medium saucepan for making cheese sauce
  • Whisk
  • 8x8 casserole dish
  • Vegetable peeler

Historical Context

While au gratin dishes have French origins, this Southern adaptation makes good use of turnips, a cool-weather crop that’s been grown across Louisiana for generations. It’s a smart way to dress up an economical vegetable for special occasions.