If you were to ask me if I have a signature holiday dish (ask me! ask me!), I would give you a resounding “Yes!” and point you to these caramelized onion crostini.
They have been a part of every single one of my holiday meals since 2009 and I fully intend to continue the tradition for as long as there are onions to caramelize and baguettes to toast in this world.
2009 was the year of my very first Friendsgiving and there is dated, photographic proof of the event. (Although, I’ll spare you the pixelated glory from my point-and-shoot camera.) My friends and I were in our first year of college and I hosted the party at my parents’ apartment (duh).
I’d prepared the works: turkey, stuffing, potatoes, gravy. The caramelized onion crostini were the wildcard, likely inspired by something I’d seen on the Food Network. To everyone’s astonishment – especially mine – they were the most popular thing on the table. No one could fathom that good ol’ humble onions could turn into such sweet-savory magic.
In the past 11 years, the crostini have undergone several evolutions. First, I swapped out the original goat cheese for my beloved plant-based spreadable “cheese”: cashew ricotta. Second, I upgraded the caramelized onions with a splash of balsamic vinegar, whose fruity tang balances the onions’ earthy sweetness.
Even more great news: all three components (toasts, cashew ricotta, caramelized onions) can be made in advance. The toasts can be cooled and kept in an airtight container at room temperature; the ricotta and onions should be stored in the fridge.
I usually prep everything the morning of the party. That way, when guests arrive early (or rather, when my cooking inevitably runs late) and ask if they can help in the kitchen, I direct them to crostini assembly while they sip on their first drinks.
How to Caramelize Onions
Caramelized onions have an intense sweet-savory flavor and jammy, pasty texture. The point is to coax out and reduce the onions’ moisture and gently (very gently!) cook them down. The process takes about an hour and requires patience.
There are two steps involved. First, you cook sliced onions in a skillet covered with a lid. This traps the onions’ moisture inside and allows them to soften. Then you uncover the skillet and cook the onions over a very low flame for up to an hour.
You do not want the onions to brown, nor become crispy. You want a slow softening process and a gradual transformation from white to caramel-colored onions. If you notice your onions browning too fast, lower the heat. If they’re drying out, add a tablespoon of water to the pan.
No matter how big or small your celebrations this season, I hope you’ll get to try this appetizer. (Or bookmark it for next year!)Print
Balsamic caramelized onion crostini with creamy cashew ricotta cheese. The perfect vegan holiday appetizer.
For the Cashew Ricotta
- 1 cup raw cashews
- 1 tablespoon fresh lemon juice
- 2 teaspoons white miso
- 1 small garlic clove
- 1/4 teaspoon fine sea salt
For the Crostini
- About 3 tablespoons extra virgin olive oil, divided
- 6–7 small yellow onions (about 1 3/4 pounds), thinly sliced
- 1 teaspoon dried thyme
- 1/4 teaspoon fine sea salt
- 1/4 teaspoon freshly ground black pepper
- 1 tablespoon balsamic vinegar
- 1 baguette, cut into 1/2-inch-thick rounds
- Start the cashew ricotta. Place the cashews in a bowl and cover with boiling water. Soak for at least 30 minutes.
- Preheat the oven to 375ºF.
- Meanwhile, start the onions. Heat 2 tablespoons oil in a large non-stick skillet over medium heat. Add the onions, thyme, salt, and pepper, and toss to coat. Cover tightly with a lid and cook until the onions have released some of their liquid, about 5 minutes.
- Uncover, reduce the heat to very low, and cook until the onions are brown, pasty, and mostly broken down, about 1 hour. If the onions start to look too dry, add a tablespoon or 2 of water to the pan.
- When the onions are done, stir in the vinegar, and cook for 1 minute more. Turn the heat off and set aside.
- Meanwhile, place the baguette slices on a baking sheet in a single layer and lightly drizzle with olive oil oil. Bake until lightly golden, 8 to 10 minutes.
- Finish the ricotta. Drain the cashews and place in a food processor or Vitamix. Add the lemon juice, miso, garlic, and salt. Pulse until everything is broken down. Add 1/4 cup water and continue pureeing until the mixture is creamy and homogeneous but not totally smooth (it should resemble ricotta, basically). Taste and adjust the seasonings if needed.
- To assemble, spread about 2 teaspoons ricotta on each toast and top with a heap of onions. Serve immediately.
- Serving Size: 1 piece
- Calories: 99
Keywords: caramelized onions, cashews, ricotta, vegan, crostini