Trim and slice mixed peppers into 1/2" strips. Peel and cut carrots into 1/4" sticks. Break cauliflower into small florets. Halve cherry peppers and olives. Thinly slice 6 garlic cloves. Place all vegetables and olives in a large heatproof bowl or jar.

Make pickling brine

In a small saucepan, combine 1 cup white wine vinegar, 1 cup water, 2 tablespoons kosher salt, and 1 tablespoon granulated sugar. Add 1 teaspoon whole black peppercorns, 1 teaspoon dried oregano, and 1 teaspoon red pepper flakes. Bring to a simmer over medium heat, stirring until salt and sugar dissolve. Remove from heat and let cool 2 minutes.

Assemble and quick-pickle

Pour the hot brine over the prepared vegetables so they are fully submerged. Press down with a small plate or nonreactive weight if needed. Let sit until cooled to room temperature, then cover and refrigerate at least 24 hours for best flavor (can be used after 6 hours for a quicker result). Keeps refrigerated up to 3 weeks.

Garlic Herb Oil

Whisk 3 tablespoons extra-virgin olive oil with 2 minced garlic cloves, 2 tablespoons chopped parsley, 1 tablespoon chopped oregano or basil, 1 teaspoon lemon zest, 1 teaspoon sea salt and 1 teaspoon freshly ground black pepper in a small bowl. Let sit at room temperature at least 10 minutes so flavors meld. If you prefer a milder garlic note, briefly warm oil (30 seconds) in microwave then cool before combining.

Whipped Feta-Boursin Spread (Creamy)

Blend cheeses

Place 6 oz crumbled feta, 4 oz Boursin, and 2 oz softened cream cheese into a food processor. Add 2 tablespoons Greek yogurt, 1 tablespoon olive oil, and 1 teaspoon fresh lemon juice. Process until very smooth and creamy, scraping down sides once or twice (about 45–60 seconds total).

Finish

Taste and adjust seasoning with up to 1 teaspoon more lemon juice or a pinch of salt if needed (Boursin and feta are salty; often no extra salt required). Transfer to a serving bowl and garnish with 1 tablespoon chopped chives and a light drizzle (about 1 teaspoon) of the garlic herb oil prepared earlier.

Bread & Assembly

Preheat oven to 375°F (190°C) if toasting bread. Brush focaccia pieces and baguette slices lightly with butter or olive oil and place on a baking sheet. Toast 6–8 minutes until warmed and edges start to color. Remove and let cool slightly.

Spread about 1–2 tablespoons of the whipped feta-boursin spread onto each piece of toasted focaccia or baguette slice. Top generously with a spoonful (about 1–2 tablespoons) of pickled giardiniera — include peppers, a small cauliflower floret and an olive for visual variety. Drizzle a little garlic herb oil (about 1/2 teaspoon per crostini) over the top.

Arrange assembled pieces on a platter. Offer remaining pickled giardiniera in a bowl with tongs or small forks and leftover whipped spread for guests to add more. Garnish platter with extra chopped parsley if desired and serve immediately.