A golden, oven-baked frittata layered with tender sliced potatoes, sweet caramelized onions, and fresh thyme — this simple yet elegant dish is perfect for brunch, lunch, or a cozy dinner. With its rustic charm and rich flavors, it offers a satisfying vegetarian option that is both nourishing and versatile.

Why You’ll Love This Recipe

This frittata is a celebration of classic ingredients that come together in a beautiful, flavorful dish. The slow-cooked caramelized onions bring sweetness, the potatoes add heartiness, and fresh thyme infuses the entire frittata with subtle herbal notes. Whether you’re hosting guests or meal-prepping for the week, this dish is easy to make, naturally gluten-free, and delicious served warm or at room temperature.

Ingredients

(Tip: You can find the complete list of ingredients and their measurements in the recipe card below.)

olive oil
butter
yellow onions, thinly sliced
Yukon gold potatoes, peeled and thinly sliced
large eggs
milk or cream
crumbled goat cheese or feta (optional)
fresh thyme leaves
salt and pepper

Directions

1. Preheat oven to 375°F (190°C).
2. In a large oven-safe skillet, heat olive oil and butter over medium heat. Add the sliced onions and cook, stirring frequently, for 15–20 minutes until caramelized and golden brown. Remove half the onions and set aside for topping.
3. Add the sliced potatoes to the skillet with the remaining onions. Sauté for 5–7 minutes until the potatoes are just tender. Season with salt, pepper, and thyme.
4. In a mixing bowl, whisk together the eggs, milk or cream, and goat cheese or feta, if using.
5. Pour the egg mixture evenly over the potatoes in the skillet, gently tilting the pan to distribute the eggs throughout.
6. Arrange the reserved caramelized onions on top. Transfer the skillet to the oven.
7. Bake for 15–20 minutes, or until the eggs are set and the top is lightly golden.
8. Allow the frittata to cool slightly before slicing. Garnish with additional thyme leaves and serve warm or at room temperature.

Servings and timing

Servings: Serves 4–6
Prep Time: 20 minutes
Cook Time: 35 minutes
Total Time: 55 minutes

Variations

• Add Greens: Stir in sautéed spinach or kale before adding the eggs for extra nutrients.
• Cheese Variations: Substitute goat cheese with shredded Gruyère, cheddar, or Parmesan for a different flavor profile.
• Meaty Twist: Add diced cooked bacon or pancetta for a smoky addition.
• Herb Swap: Use rosemary or chives instead of thyme for a new aromatic direction.
• Mini Frittatas: Bake the mixture in muffin tins for individual portions perfect for meal prep or entertaining.

Storage/Reheating

Store leftover frittata in an airtight container in the refrigerator for up to 4 days. Reheat slices in a 325°F (165°C) oven for 10–15 minutes, or warm gently in a nonstick skillet over low heat. Avoid microwaving to preserve the texture. This dish can also be enjoyed cold or at room temperature.

FAQs

Can I make this frittata in advance?

Yes, it can be made ahead and stored in the fridge. Reheat gently before serving or enjoy at room temperature.

What type of skillet should I use?

An oven-safe skillet such as cast iron or stainless steel is ideal for this recipe.

Can I use different potatoes?

Yes, russet or red potatoes can also be used, though Yukon golds offer a creamy texture that holds well.

Can I make this dairy-free?

Yes, use a dairy-free milk alternative and omit the cheese, or use a plant-based cheese substitute.

Why are the onions cooked separately?

Reserving some onions ensures they remain on top of the frittata, enhancing both flavor and presentation.

Can I freeze this frittata?

Yes, freeze individual slices tightly wrapped. Reheat from frozen in the oven until warmed through.

How do I know when the frittata is fully cooked?

The center should be set and no longer jiggly. A knife inserted should come out clean.

What can I serve with this frittata?

It pairs well with a green salad, crusty bread, or a side of fruit for a complete meal.

Can I use dried thyme instead of fresh?

Yes, but use only about one-third the amount, as dried herbs are more concentrated.

Is this frittata suitable for vegetarians?

Yes, it is vegetarian as written, especially if made with a vegetarian-friendly cheese.

Conclusion

The Potato and Caramelized Onion Frittata with Fresh Thyme is a hearty, flavorful dish that effortlessly combines elegance and comfort. It’s a versatile recipe that adapts to many variations and occasions, from a casual brunch to a light dinner. With its creamy texture, savory depth, and beautiful golden finish, this frittata is sure to become a staple in your kitchen.

Print