1. Preheat oven to 350°F.  Combine butter and sugar in a food processor just until well combined.  Add egg, heavy cream, vanilla, and a pinch of Kosher salt, and blend until well combined.
2. Lightly butter 2 individual ramekins.  Break apart doughnuts into bite-sized pieces and tightly layer in ramekins.  Pour custard mixture over the doughnuts (just until they are covered) and let soak for approximately 5-10 minutes.  Place a drinking glass or similar object on top of ramekins to keep the doughnuts pieces submerged in custard mixture during this time.
3. Cover ramekins with foil and bake approximately 30-35 minutes, until the custard is just set, but still soft.  Remove from oven and drizzle about 1/2 tablespoon of Chambord (or more if you want a stronger flavor) over the top of each bread pudding.  Let cool slightly.
4. When ready to serve, either keep bread pudding in ramekin and serve with a side of the Raspberry Chambord sauce, or run a knife along the edge of ramekin and unmold bread pudding by inverting onto a plate. Drizzle with Raspberry Chambord sauce.  Sprinkle with powdered sugar, if desired, for garnish.

Raspberry Chambord Sauce

1. In a small saucepan over medium-high heat, bring the raspberries, Chambord, and sugar to a boil.  Simmer for about 2 minutes, stirring frequently, until raspberries are broken down.  Pour mixture through a fine mesh sieve into another small saucepan, pushing on solids to release as much sauce as possible.  Return mixture to heat and simmer another 2 minutes, stirring frequently.
2. Meanwhile in a small bowl, dissolve cornstarch in water.  Slowly add cornstarch slurry into sauce, stirring constantly until it has thickened.  Remove from heat and chill until ready to serve.