This easy caramelized onion crostini recipe on toasted baguette slices with goat cheese and a fresh sprig of thyme, comes together in an hour!

bite of Caramelized Onion Crostini with fresh thyme

How do you caramelize onions? If you were to ask me if I had a signature holiday appetizer, I would point you to this Caramelized Onion Crostini recipe without hesitation. It’s a classic that has been around for decades, with very simple ingredients. Oh, and did I mention that these little bites get gobbled up at every party?

Caramelizing onions until they are richly browned, is a wonderful way to pull flavor out of the simplest of ingredients. Maybe you’ve tried my Caramelized Onion Brie En Croute!

Easy Caramelized Onion Crostini

The secret to caramelizing onions is that you need a little time. But with time, you get very soft and nicely browned onions – but not too dark. As you slowly cook the onions, this brings out deep, rich, sweet flavor, as the natural sugars in the onions begin to caramelize.

Make a crispy appetizer, ready in an hour.

ingredients for bite of Caramelized Onion Crostini

Ingredients needed for caramelized onions:

  • White sweet onions
  • Unsalted butter or olive oil
  • Kosher salt
  • White wine (optional)

Gather these simple ingredients for Easy Caramelized Onion Crostini:

  • Caramelized onions
  • Baguette
  • Olive oil to brush on
  • Cypress Grove Lavender and Fennel Goat Cheese (or use regular goat cheese) – print off more goat cheese appetizer recipes below!
  • Fresh thyme

bite of Caramelized Onion Crostini

How to use sweet browned onions in other recipes:

  • Quiche
  • Pizza
  • Flatbread
  • Tartlets
  • Pasta recipes
  • Grilled Cheese
  • Burgers (delish on this mini burger board)
  • Soup
  • Eggs
  • Chicken, Steak, or Pork
  • Amazing paired with hummus
  • Delicious paired with goat cheese

round plate of bite of Caramelized Onion Crostini

Which onion caramelizes best?

We’ve found that yellow or sweet onions, like Vidalia and Walla Walla, caramelize the best. You can also caramelize red onions, which are still sweet and delicious, and the purple color is great on pizzas and salads.

The texture of caramelized onions is gooey and tender. While you do have to stir the onions occasionally, you don’t have to babysit the pan, which means for this recipe, you can start by toasting the baguette while the onions are cooking. Easy peasy!

If you’ve found the onions to be mushy it’s because you sliced them too thin or too thick (the onions might get mushy before the middle is cooked through). If too thin, they burn easily or cook too quickly before you get the right flavor.

ingredients for bite of Caramelized Onion Crostini

TIPS: Use a mandolin to slice the onions

We love using this mandolin slicer, which gives the perfect slice. It’s affordable and easy to store.

I toss it in the dishwasher after each use.

Adjust the thickeness to each slice! You can buy it, here.

Also, you can skip adding the wine, but just add more water as needed toward the end of cooking so the onions don’t dry out and burn. You can cook the onions until they are very dark brown (this obviously just takes more time) for deeper flavor.

bite of Caramelized Onion Crostini with goat cheese and fresh thyme

How to make caramelized onions on the stovetop

Grab the full recipe below!

  1. Place the onions in a large pot over medium-high heat, with butter and a generous pinch of kosher salt.
  2. Cook until the butter melts into the onions and steam begins to come off.
  3. Reduce heat to low. To ensure and expedite softening, I cover the onions with a lid to build steam and keep the moisture in, stirring every so often.
  4. Once you remove the lid, cook some more. During the last 20 minutes, add the white wine and allow it to cook off.
  5. Continue cooking until the onions have reached your desired level of caramelization.

How long does it take to make caramelized onions?

Remember that making these onions requires at least 45 minutes (and often over an hour, if not more) over low heat, for the natural sugars in the onions to caramelize.

a serving of bite of Caramelized Onion Crostini

It’s the weekend! Are you hosting?

Inviting new people over for an appetizer is a tangible demonstration of, We’re not going to do the same thing over and over.

With intention and hope, we live in the now. We put the phones down.

We take in the warm sunshine, our faces to the sky, and bite into a delicious Easy Caramelized Onions Crostini, with a sip of really good wine.

You don’t need a lot of wine, just a few sips of really, really good wine.

Because really, entertaining is all about the people.

Happy weekend, Friends!

More recipes to try with goat cheese:

Goat Cheese Bacon Crostini

Strawberry Goat Cheese Bruschetta

Whipped Goat Cheese Dip

Prosciutto Goat Cheese Crostini

Apple Goat Cheese Crostini Appetizer

bite of Caramelized Onion Crostini
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Easy Caramelized Onions Crostini

This recipe is for a large batch of onions, so you can enjoy them in eggs, pasta dishes, or simple appetizers. Halve the recipe if needed.

Ingredients

Caramlized Onions

  • 4 large white onions, cut into 1/2 inch half moons
  • 6 Tbsp unsalted butter or olive oil
  • Kosher salt to season
  • 1 c white wine, optional

Crostini

  • 12 ½-inch baguette slices
  • Olive oil to brush
  • 3 oz Cypress Grove Lavender and Fennel Goat Cheese, or regular, softened
  • Fresh thyme leaves to garnish

Equipment

Instructions

Caramelize the Onions:

  • Place the onions in large pot over medium-high heat, with butter and a generous pinch of kosher salt. Cook until the butter melts into the onions and steam begins to come off. Reduce heat to low. To ensure and expedite softening, I cover the onions for about 35 minutes with a lid to build steam and keep the moisture in, stirring every 12-15 minutes. Once you remove the lid, cook for 20 minutes, stirring a few times. During the last 20 minutes, add the white wine and allow it to cook off. Continue cooking until the onions have reached your desired level of caramelization.

Make the Crostini:

  • While the onions caramelize, prepare the crostini. Use a pastry brush to lather olive oil onto both sides of the bread. Line the slices on a baking sheet and place on the center rack of the oven. Turn the broiler to 450. Toast slices for 2-4 minutes (depending on your broiler), then remove, flip the bread, and toast the other side for an additional 2-3 minutes.
  • Allow bread to cool, then spread on goat cheese, caramelized onions, and thyme leaves. Serve warm or chilled.

Notes

TIP: To quickly and evenly cut the onions, use a mandolin! I like this one.
TIP: You can skip adding the wine, but just add more water as needed toward the end of cooking so the onions don’t dry out and burn. You can cook the onions until they are very dark brown (this obviously just takes more time) for deeper flavor.
Did you make this recipe?Tag @reluctantentertainer on Instagram and hashtag it #reluctantentertainer!

bite of Caramelized Onion Crostini serving

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