Tender, sweet onions with briny olives and cheese make a great side dish or appetizer to serve on toasted baguette slices.
Makes
4 cups
Total Time
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Ingredients
Test Kitchen Approved
Test Kitchen Tip
Choose sweet onions for this recipe, such as Vidalia, Walla Walla, or Maui.
Instructions
Preheat oven to 400°.
Melt butter in a large cast-iron or other ovenproof skillet over medium heat. Add onions, stirring until slightly softened; cover and cook until completely softened, 10 minutes.
Add sherry, thyme, and bay leaves; increase heat to mediumhigh. Sauté, uncovered, until the liquid evaporates and onions are browning, stirring occasionally, 10–15minutes.
Combine Parmigiano-Reggiano and Gruyère, then stir ½ cup of cheese mixture into onion mixture. Top with remaining ½ cup cheese and bake until cheese is bubbly and browned, about 20 minutes.
Remove and discard thyme sprigs and bay leaves. Sprinkle olives over onions and let cool slightly. Serve Onions au Gratin with baguette slices.
Test Kitchen Approved
Nutritional Facts
Nutritional Facts
Per 1/4 cup
Calories: 70
% Daily Value*
Total Fat 4g 6%
Saturated Fat 2g 10%
Cholesterol 10mg 3%
Sodium 103mg 4%
% Daily Value*
Carbs 6g 2%
Fiber 1g 4%
Protein 3g
*Percent Daily Values are based on a 2,000 calorie diet.