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These crostini are crisp toasts spread with creamy Boursin, topped with a fold of warm pastrami and a spoonful of jammy caramelized onions. They are the easy appetizer everyone hovers around.
Every bite has something going on. The cheese is garlicky and soft, the pastrami is salty with crispy edges, and the onions bring the sweetness.
The onions are the only part that takes time, and they can be made days ahead. Serve them with my Deviled Eggs with Candied Bacon for an easy appetizer spread.
What Goes Into These Crostini
- Baguette. One French baguette, sliced 1/2 inch thick on a slight angle.
- Boursin. Two packages of Garlic and Fine Herbs, softened so it spreads easily.
- Pastrami. Eight ounces, thinly sliced. A quick sear gives it crispy edges.
- Onions. Three large yellow onions, slowly caramelized with butter, a little brown sugar and balsamic.
- To finish. Chopped chives, plus whole grain mustard or hot honey if you like.
How to Make Them
Caramelize the onions. Cook them low and slow for 35 to 45 minutes until deep golden and jammy. Add the sugar and balsamic at the end.
Toast the bread. Brush with olive oil and bake at 400°F until golden and crisp.
Warm the pastrami. A dry, hot skillet for 30 to 60 seconds, just until the edges crisp.
Assemble. Boursin, then pastrami, then onions, then chives and a drizzle.
Tips
- Do not rush the onions. High heat burns them before they turn sweet. Add a splash of water if they stick.
- Fold the pastrami loosely. It gives every toast some height and looks better on the board.
- Assemble close to serving. The toasts stay crisp for about an hour once topped.
Make Ahead and Storage
The onions keep up to 3 days in the fridge, so rewarm them before using. The toasts can be baked a day ahead and kept in an airtight container. Assemble the day of.
Frequently Asked Questions
Can I use another cheese?
Whipped cream cheese with garlic and herbs works, or a soft goat cheese.
Can I use corned beef or roast beef?
Yes. Pastrami is the smokiest, but both are good.
How many should I plan per person?
About 3 to 4 if there are other appetizers.
More for the Holiday Table
Holiday Recipes
Candied Yams with Marshmallows
Side Dishes
Cornbread Dressing
Holiday Recipes
Roasted Cajun Turkey Recipe
Dessert
Honey Butter Cornbread
Pastrami, Boursin and Caramelized Onion Crostini
Ingredients
- 2 tablespoons unsalted butter
- 1 tablespoon olive oil plus more for brushing
- 3 large yellow onions halved and thinly sliced
- 1/2 teaspoon kosher salt
- 1 teaspoon light brown sugar
- 1 teaspoon balsamic vinegar
- 1 French baguette sliced 1/2-inch thick on a slight angle
- 2 packages Boursin Garlic and Fine Herbs 5.2 oz each, softened
- 8 oz thinly sliced pastrami
- Fresh chives finely chopped, for garnish
- Whole grain mustard or hot honey for drizzling, optional
Instructions
- Caramelize the onions. Melt the butter with the olive oil in a large skillet over medium heat. Add the onions and salt and cook, stirring every few minutes, for 35 to 45 minutes until deep golden and jammy. Add a splash of water if they start to stick. Stir in the brown sugar and balsamic for the last 5 minutes.
- Toast the bread. Heat the oven to 400°F. Arrange the baguette slices on a sheet pan, brush with olive oil and bake 8 to 10 minutes until golden and crisp.
- Warm the pastrami. Cut the pastrami into pieces about the size of the toasts. Warm in a dry skillet over medium-high heat for 30 to 60 seconds until the edges just crisp.
- Assemble. Spread each toast with Boursin, top with a folded piece of pastrami and a small spoonful of onions. Finish with chives and a light drizzle of mustard or hot honey, if using.
