This is an unusual combination, but the bright, spicy bite of peppercorns and rhubarb cuts the cheese's creaminess. Trim off any rhubarb leaves, which are toxic, but leave the cheese rind on.
1 pound rhubarb stalks, leaves trimmed and discarded, stems sliced 1/4 in. thick
5 tablespoons honey
1 teaspoon balsamic vinegar
1 heaping tbsp. green peppercorns in brine, drained
1 French baguette (at least 14 in. long)
2 tablespoons olive oil
11 ounces very ripe triple-cream cheese such as Marin French Cheese Company Rouge et Noir Triple Crème Brie, or other brie or camembert, at room temperature
How to Make It
Cook rhubarb with honey in a medium saucepan over medium heat 6 to 8 minutes, stirring occasionally, until rhubarb is very soft and just starting to fall apart. Preheat oven to 350°.
Remove pan from heat and add vinegar and peppercorns; let sit at room temperature (so flavors meld) at least 1 hour.
Slice baguette meanwhile on the diagonal into 1/2-in.-thick slices to make Put slices on a baking sheet, brush one side with oil, and bake until golden brown, about 15 minutes. Let cool.
Cut cheese into 26 thick slices, each about as long as a baguette slice.
Spoon a scant 1 tbsp. rhubarb mixture onto each baguette slice. Top each with a slice of cheese (or two smaller pieces) and serve immediately. Or serve toasts, topping, and cheese separately and let guests assemble the crostini.
Make ahead: Toasts, up to 1 day, stored airtight at room temperature; rhubarb topping, up to 1 day, covered and chilled.